Advise needed: Air Shocks

My '71 Dart GT was originally 318 ci equipped but later had a 340 dropped into it prior to me buying it, and I've found a huge difference in handling by changing out all of the above components you mentioned. It's a weekend Driver and I've replaced:
1. front and rear shocks (KYB in the back)
2. ball joints
3. front & rear sway bars
4. rear leaf springs
5. torsion bars
It had air shocks on it when I got it, and I (stupidly) replaced them with a set of Monroe air shocks which I could never get to stop leaking. I finally pulled those off and put a set of KYBs on when I did the springs. Even though it's a Driver, the replacement components have made a huge difference in handling. Good luck with yours.
As an afterthought, yours would definitely benefit from replacing the original torsion bars with a beefier set made to accomodate the weight of the 383, IMHO.