Here's my general rule of thumb . . . the rocker panel needs to be parallel to the ground (flat surface). If you look at factory pictures, you'll also see that if you extend a line from the lower rocker panel side through each of the wheels on that side, there is a general relationship of where that line crossed the center of the wheel cover/hub cap, too.
Then follow the procedure in the FSM to ensure the front end is at the correct height on each side. If the rear is low after doing this, then some way to raise the rear can be investigated.
Several of the earlier Fuselage cars' body designs have a natural wedge to them. Lowering the front a slight bit can accentuate that. BUT, there are consequences for lower the front end NOT related to the way things look.
First thing is that lowering the front suspension ride height results in a softer ride rate for the front suspension. Just as raising the level results in a stiffer ride rate. Just the nature of torsion bars.
The other thing is that lowering or raising the bars can affect front end alignment, especially effective caster (which helps the car go in a straight line and self-centers the steering wheel after a turn). Not to forget that the decreased ride height can make the front end bottom out sooner on a dip or big bump.
On Fuselage cars, lowering the front also raises the level of the rear bumper. Which can put the fuel tank in a bit more peril in case of a rear end collision. That rear valence panel is the main thing between the rear body and the fuel tank. Unlike the Slabs which came before them.
Personally, at my semi-advancing age, I remember when Chryslers were about "road cars" and not "profiling boulevard cars" (think GM cars from the '50s and '60s with their soft suspensions!). The natural cruising speed of our '66 Newport (factory a/c) turned out to be 75-90mph. Below 75, it was bored. Over 90, the factory suspension got "busy", even with HD shocks. And . . . it was fun to drive around corners that would leave a Ford (especially) with squealing front tires and GMs with massive body lean, just trying to keep up . . . if they could. All while providing a firm but comfortable ride. And, with the 2.76 rear axle ratio, the engine was at or near the top of the torque curve, so engine response was good, as was fuel economy.
Yes, I like wheel travel so the suspension bump stops are used very rarely, if ever. Front and rear.
One thing which Chryslers tend to have, which other brands do not, is longer front and rear overhangs of the body. Which means they might scrape the bumpers quicker on driveway approaches. Just as a lowered ride height can "high center" over humps. Each requiring driving into and over those things differently. BTAIM
Until you've driven Chrysler Corp cars for hours at a time on the Interstate or state highways, noticing how the steering reacts, how tight the throttle response can be, and how the car likes what it's doing, plus comparing that to similar Ford or GM cars, you might not fully appreciate what makes a Chrysler product a Chrysler product. The great road cars they were and still are.
But if most of your driving is in a metro area, many of these attributes just vanish as the car is more of an appliance than a neat vehicle to drive. No issues with "hot soak re-start" while running down the road at 75mph, for example. As civilization expands, as to the metro areas, more "slow speed" highways rather than "open roads". "Slow speed" roads where any car can do well.
Y'all enjoy!
CBODY67