'Grabby' brakes

Even when new, the Chrysler power brakes were notorious for being touchy.

I like things simple so I'm running 73-76 disc brake with 10"x2-1/2" in the rear MANUALLY on my 68 cuda. Unless you have a physical condition that limits your leg strength, I would recommend the same for you. A 73-76 power brake MC run manually (no booster) has a 7/8" bore and results in excellent linear feel. You would need a manual MC pushrod with this setup or an aftermarket adjustable one. Everybody who does this likes it.