Adding Gauges to my 300L

[Big_John]

Typical of most C-bodies, this car doesn't have an oil pressure or temperature gauge. I've figured my old cars should have those two gauges, plus a voltmeter.

I've never been one to just bolt in some gauges. I like to see them look appropriate to the interior of the car. For example, my '65 Barracuda has a fairly spartan dash, and given the nature of the car, some old school Stewart Warner gauges in a chrome bezel look just right (to me anyway).

The 300L's dash is not what you would call spartan, it's kind of a blend of more modern with some early 60's "Astradome" flavor. Adding gauges and having them fit and look correct was going to be a challenge.

The fit problem lead me into using 1 1/2" gauges rather than the traditional 2" gauges. I've used Autometer's "Autogage" setup in my '70 300 and while it never looked good, it did the job well and wasn't too obtrusive.

So... I pulled the gauges out of the '70 and started trying some test fits. Using my 3D printer, I tried some simple gauge mounting and when I was happy, I designed the mounting bracket and bought some new gauges from Amazon.

This was the test piece I was happy with. It used the existing holes and kind of covered the fugly screws that Chrysler used for attaching the vacuum gauge to the console. Win-win.

My final print, done in Pet-G plastic. I primed with a filler primer and a little sanding later, it was painted flat black.

 

[pomonamissel]

my bud did this sorry about the through the glass pics

 

[Big_John]

The gauges... I never liked the face. The little oil can and thermometer just rubbed me the wrong way... So I changed it.

First the gauge bezel had to be removed. If you've ever tried to do this, it's real easy to screw it up... Especially the aluminum bezels these gauges have. I've seen guys use hose clamps around the bezel to prevent damage to the outside and instead of that, I printed something the gauge sets into that holds the outside of the bezel.

Here you can see where I've started to remove the bezel.

With the gauge apart, I sanded off the offending picture and painted them flat black.

Mocking it up, it looked a little plain.

One thing lead to another and with some help from Mrs. Big John and her new Cricut machine, I added the red, white, and blue circle that you see on 300s. I wanted to get a little more detailed, but decided "less is more" and keep just the circle. Since the bezel got a some scuffs on the front edge from handling, I took a real fine piece of sand paper to the edge and created a silver ring that I think sets the gauge off a little more.

Glass and I have a strained relationship at times, so breaking the glass face on one didn't surprise me. I found a guy that cuts round glass circles on Etsy and they are in the mail. In the mean time, I decided I want to do this with the '70, so I had 6 gauges all apart and just grabbed another glass under the replacement gets here.

The bezel being crimped back in place...

This was before I finished, most of the wrinkles are gone.

 

[Big_John]

I wanted to check the new gauges before I tore them apart and also check any that I had finished. I found the values that the senders (these are electrical gauges) put out on a somewhat hidden Autometer page.

I set up my resistor decade box and used my "no cost" power supply that I salvaged from an ancient computer.

New ones were spot on, a couple of the used ones needed a little tweaking, but were still in the "close enough" range when I first checked them. Note the use of highly technical metrology term "close enough". No, nothing was NIST traceable and I wasn't concerned with test accuracy ratio or measurement uncertainty. That was crap I used to have to worry about.

To adjust the gauge, there was a little pot that you can see in the hole for the light.

Wired up using a real simple harness. A plug will be used to connect it to the car so I can easily remove it. I had those gauges out of the convertible more times than I cared to. It's getting a plug too.

Finished gauges and bracket.

Installed... I still have to install the senders and wire to the gauge. I think it ties together OK.

 

[3175375]

Nice job!

 

[commando1]

John, your obsession to doing things perfectly is always amazing to me. Outstanding work!!

 

[Mike66Chryslers]

Beautiful job! The gauges look right at home.

 

[Samplingman]

Excellent work as usual.

I've been thinking about doing something similar, only using the dash blank where the rear defog switch would go. I'm looking at some vintage gauges from a B body or maybe the rectangular ones from a '70 Imperial.

 

[Big_John]

I've been thinking about doing something similar, only using the dash blank where the rear defog switch would go. I'm looking at some vintage gauges from a B body or maybe the rectangular ones from a '70 Imperial.

After I had the dash in my '70 all done, I had an idea of finding a '70 Imperial dash and using the entire cluster in my car. It was a little late in the game as I had already put the entire dash back in. There would be some electrical to figure out, but I think it could be done.

I had these in the '70 and now I'm going to look at a different spot. At the time I wasn't retired and just getting some gauges in the car was the idea as I didn't have the time to mess with it. I really disliked it, but I lived with it. I'll probably modify my design from the 300L so it'll bolt to the bottom of the dash.

 

[live4theking]

So which order are you going to have them in when they go in the car? Or maybe you don't have a preference, but I doubt that.

 

[Big_John]

So which order are you going to have them in when they go in the car? Or maybe you don't have a preference, but I doubt that.

You guys are really getting to know me. LOL.

Actually, I did kick that one around a little.

I figure voltage isn't something I need to check all the time unless there's something that points me to needing to check it, so that's the farthest away.

Oil pressure is monitored a little more closely, always at start up, but the idiot light is still there. That went in the middle.

That leaves temperature and something that I tend to pay attention to if the car is doing some extended idling in traffic, so that goes closest, or on the left. Again, the idiot light is still there.

Now... If this was something where I had to monitor these gauges all the time, they would be the larger 2 5/8" gauges, be mounted closer to my line of sight while driving and the gauges would be rotated so the optimum reading was at 12:00.

 

[Boydsdodge]

Looks great. When I started reading your post, I said to myself Ugghhh, don't like the trade name and symbols on the gauge faces. All happy in the end.

 

[Trace 300 Hurst]

Typical of most C-bodies, this car doesn't have an oil pressure or temperature gauge. I've figured my old cars should have those two gauges, plus a voltmeter.

I've never been one to just bolt in some gauges. I like to see them look appropriate to the interior of the car. For example, my '65 Barracuda has a fairly spartan dash, and given the nature of the car, some old school Stewart Warner gauges in a chrome bezel look just right (to me anyway).

The 300L's dash is not what you would call spartan, it's kind of a blend of more modern with some early 60's "Astradome" flavor. Adding gauges and having them fit and look correct was going to be a challenge.

The fit problem lead me into using 1 1/2" gauges rather than the traditional 2" gauges. I've used Autometer's "Autogage" setup in my '70 300 and while it never looked good, it did the job well and wasn't too obtrusive.

View attachment 626364

Big_John, it seems that confused and obsessive minds think alike. I also felt that the "Day Two" look had to be proper, whatever that meant. Indeed, I removed the inappropriate 60's chrome gages that were installed sometime in the prior 50 years.

The provided bracket worked just fine for me, but your craftsmanship for your cluster is very cool. I agree about the trade names on the faces (but didn't we all just LOVE that Sun emblem instead of Sears or something generic on our tachs?) but I liked the icons to quickly identify what I'm looking for. Recall that old gages would say Oil, Temp, Volts, etc. which was good from my POV.

 

[straightjob]

Typical of most C-bodies, this car doesn't have an oil pressure or temperature gauge. I've figured my old cars should have those two gauges, plus a voltmeter.

I've never been one to just bolt in some gauges. I like to see them look appropriate to the interior of the car. For example, my '65 Barracuda has a fairly spartan dash, and given the nature of the car, some old school Stewart Warner gauges in a chrome bezel look just right (to me anyway).

The 300L's dash is not what you would call spartan, it's kind of a blend of more modern with some early 60's "Astradome" flavor. Adding gauges and having them fit and look correct was going to be a challenge.

The fit problem lead me into using 1 1/2" gauges rather than the traditional 2" gauges. I've used Autometer's "Autogage" setup in my '70 300 and while it never looked good, it did the job well and wasn't too obtrusive.

View attachment 626364

So... I pulled the gauges out of the '70 and started trying some test fits. Using my 3D printer, I tried some simple gauge mounting and when I was happy, I designed the mounting bracket and bought some new gauges from Amazon.

This was the test piece I was happy with. It used the existing holes and kind of covered the fugly screws that Chrysler used for attaching the vacuum gauge to the console. Win-win.

View attachment 626365

View attachment 626366

View attachment 626367

My final print, done in Pet-G plastic. I primed with a filler primer and a little sanding later, it was painted flat black.

View attachment 626368

Wow you have the same cars I have! I want to do the same I know nothing of 3D printers ugh

 

[straightjob]

Wow you have the same cars I have! I want to do the same I know nothing of 3D printers ugh

 

[fury fan]

Excellent work, @Big_John!
I love the sanded ring of shiny metal and the tri-color decals from the Cricut.
Cool to learn you have a 3D printer for such shenanigans. I've got a CNC router that I've used for some car stuff.

A 300L is a tough one for adding gauges as the console's vacuum gauge limits some options.
Not meaning to steal your thunder, but here are some of my poor attempts in my 300L.

Here's a 4-pod thing I got from amazon, attached to some plastic sheet I CNC'd to mount in the pull-out ashtray. Has 4 switches also.
Ultimately it would get thicker plastic to hold the curvature better, and 1-piece aluminum trim with countersunk screws to mount it. (I also devised 2 mounting tabs at the top-middle to hold it better.

But I wasn't fully satisfied with it because I also want a radio somewhere.

So I evaluated a 1960 Plymouth speedo housing I got some years ago for another car.
I had already CNC'd a piece of wood to fit into it, and holds 4 2-5/8" gauges. Would need to change that wood to aluminum, of course.
It fills the hole from the ashtray, and I think just needs some suitable mountign straps that span the void top-to-bottom.
But it's pretty wide, and does protrude a bit toward the passenger's knee.
The knee in the picture is really stretched out, to hold it in place for a picture. Normally-sitting, there would be 6-8" of clearance.
And 99% of the time I drive alone, and the protrusion only matters in case of an accident and with a passenger.
But this one won't hold a radio either.

So I am still undecided on what I want. The void from the pullout drawer provides a unique location, but it's a bugger to mount to and make it look somewhat factory-installed.

Perhaps a radio goes in the ashtray area, and 4 gauges (including vacuum) could be mounted to cover teh factory vacuum gauges ala late 60s GM.