The M bodies came along about 4 years after the first F body showed up. Chrysler had more money, and 4 years to correct a few issues. Harder rubber mounts, thicker upper control arm brackets with some support, and bigger sway bars. Even the later F bodies and the J bodies in between the early F & the M were better handling cars then the early F bodies were.
Glad you know what I am talking about
I always thought "They definitely did something, and Whatever they did, it worked" and never went past that point.
Cool to hear about some of the changes they made.
