Nice car, I like it.
If you swap out that master cylinder, save the old one!! That extension on the top of the one on the car is for added capacity for the disc brakes and is hard to find.
Trans leak is probably the shifter seal. They mimic a pan leak because it drips down. I suggest a look at this thread.
TF 727 "How To" shift lever seal replacement and use the Chrysler trans pan gasket PN# 02464324AD if you have the pan off
A/C could be anything... Since that's a add-on knee knocker, you might want to look at a rotary Sanden (or Sanden clone) compressor.
I have to comment on the color change. Full disclosure, I love black cars and I also have sworn off them for the sake of my sanity. Ever own a black car? The upkeep is insane. You might as well keep a microfiber towel and detail spray handy at all times. I would bet you guys get a lot of that same yellow pollen that we get here (I'm near Syracuse, NY) and you can start at one end of the car, get it all wiped down and then the pollen makes it a mess before you can put your detail stuff away. A color change to black is also going to be expensive if done correctly. I'll bet $20K USD for a good job. I still love black cars though...
Since this is you first restoration, that car doesn't look like it needs much. My advice FWIW.... Get the brakes working and whatever it need to be safe and then drive it a while. Have some fun with it first. Then take on small tasks that won't take it off the road for more than a day. You'll be much happier with a driving car that might not be quite perfect than you will with a car that's all apart and sitting in the garage.