Upgrading front suspension in my 64 cuda

The a body suspension is pretty well designed.
Upgrading to 73 and new front disc brake, which you need the upper control arm (I bought a tubular control arm) and spindle and brake hardware. You could also up grade to full size cordoba rotors just need rotors caliper and caliper brackets.

Tires are the most important part of handling so widest and stickiest you can fit all around.
Next is to keep the tire flat through the turns which shocks, spring rates ( torsion bars and leaf springs) sway bars and cars weight balance has everything thing to do with that along with center of gravity, roll centers etc..

I'd start with a big front sway bar then take it out autocrossing and see where it needs improving and go from there. Don't for get there's rules to be followed.