Why is it that, respectfully, people buy a nice car, even a LOW PRODUCTION body style, and immediately start wanting to change it? Kind of like some females I've known of who dated a guy all through high school and college, then they get married and SHE wants to change him, remake him in HER desires?
Air bag suspension. Can be done on Chrysler vehicles of this vintage, gut it's quite a bit more than a similar GM car. One of the GREAT things about these cars is their ride and handling, especially when compared to Ford and GM cars of that era!! But you weren't around back then, so you might not know that. ONE reason to get to know the car and what made it the great cars they were BEFORE spending large amounts of money to make it "trendy" in some circles of friends.
The OTHER thing is that it's NO FUN having to take extra pains to drive such that you don't drag the rear bumper when entering driveways or similar. OR drag the middle when going over humps that other cars can just drive over. Might look kewl, but not to those behind you.
Several years ago, I was behind some younger guys in a Honda that they'd torched the coils on to lower it. It bobbed down the road on each small bump. THEN, when they came to a railroad track, they danged near had to stop to inch over it! THAT is a traffic hazard!!! Plain and simple.
If you want the big wheels, then you'll have to deal with the restricted turning issue of hitting bumps in the middle of the turn, very possibly. Tire/sheet metal noises are not kewl, either! Might even rip the wheel opening moldings on the front fenders, not to mention gouges in the tire. Take the time to get a taller lower control arm bumper, then trim it down so that it bottoms-out the front suspension so the tire/sheetmetal situation doesn't happen.
NOT to forget that it might also rub on the inner fender section, too. End result, the turning diameters on these Chryslers are wide enough as it (wider than similar Ford and GM cars), so making it wider because of your wheel/tire choice can make maneuvering in tight spaces a pain AND glad it has good power steering.
If you want to do these things to a vintage classic car, I'm presuming you purchased the car for that reason rather than because it was a Chrysler only? It's much easier to make those things happen on a GM car than on a Chrysler. MUCH easier to do the air bag deal, for sure!
Now, in the Drydock forum, there's a thread where a guy did the air bag deal/4-link on a '66 Newport. It all went in much easier than I'd ever have suspected. BUT dealing with the front suspension is much more difficult, due to the way things are designed. And, in the process, you get rid of the torsion bars, which are ONE of the reasons the cars ride/drive so nicely . . . AND turn corners flatter than other similar GM cars did. Plus the superior Chrysler front end geometry!
IF you are going to use wheel spacers to correct for incorrect wheel backspacing, you'll need some LONGER wheel studs! AND you'll also need to change ALL of the studs to the later RH thread, as the current ones have LH thread on the LH side of the car. MUCH better to get wheels with the correct backspacing, period!
It's your car and you can do whatever floats your boat with it, BUT at least learn about it BEFORE you dive head-long into doing a bunch of stuff that your friends (or people who might perceive you want to be your friends) might like. If and when they might move on, you've still spent a lot of money "for nothing", even if it did make you feel good to do it.
The other thing is that the things you're considering doing/have done do NOTHING to increase the value of the car on the open market. Quite the opposite. Don't do anything that you can't revert to easily. That's a time-honored observation. Banks/finance companies don't like modified vehicles, either, so you'll need to find somebody that likes exactly what you've done to the car AND can pay cash.
IF you're wanting something to customize and such, look for a Buick as they have some much better lines for custom paint and such.
Respectfully,
CBODY67