My wife says her 72 challenger was the best driving riding car.
Without driving or riding shotgun I'd suggest dump all the poly and go back to rubber, get some good shocks (not performance). Good tires properly inflated, aligned and perhaps put highway gears in it. I think I ended up with 293's living in the mountians, drop to 2nd (auto no kit) and never touched the brakes running downhill on one of the twistiest highways in nor cal.
I also added some nice soundproofing, quiet, low restriction exhaust and a nice stereo. She loved that car and still brings it up even though it's been gone 20 yrs.