I have read good things about KYBs for years. At this time, almost all normal shocks will have been "low gas pressure", mainly to reduce fluid foaming internally, for about a decade or so. It;s not specifically this low gas pressure that might improve the normal ride/handling performance, but the shock's internal valving, as always. But any gas pressure will help push teh wheel "down" for better tire/road contact at all times, which is a plus and can give the car a more stable feel on rougher roads.
As mentioned, tire pressure and tire choice make a difference, too. I like to run my tire pressures 32/30, f/r, for a firmer ride and sharper turn-in performance. TWO things which Chrysler suspensions are known for. Plus better equalizing f/r tire wear, by observation. Adjusting tire pressure to reflect the greater percentage of the weight on the front end vs. the rear end and the factory recommendations.
Actually, from what I discovered in the Chry parts book, there are 3 different suspension calibrations. The "base"/std would be the basic 383 car without factory a/c. When factory a/c is ordered, the HD front torsion bars are added to supporrt the added weight of the a/c items, but with the normal front shocks. When the HD suspension is ordered, that kicks in the HD rear leaf springs and HD shocks. There were "High Control" shock abs options, which were usually normal 1" bore shocks with stiffer internal valving as there was a HD Shock option that used something like the HD Monroe Super 500 shocks with larger rear pistons.
My '66 Newport has the factory a/c suspension, to which we added full HD Chrysler (parts) shocks many years ago. Works fine, especially with my tire pressure tweaks. They are still on the car, decades later.
In modern times, the KYBs seem to be the best option.
CBODY67