Sounds like a good driver. My opinion is to drive it but make it safer like adding disc brakes if it has 4 wheel drums. No need for power brakes on these cars even with front discs. Power brakes do NOT improve braking performance.
Drive it and the car will tell you what it needs. And why does everyone automatically want to put a v8 in a /6 car? I won a 2nd place trophy last year in a class of 20 cars at a big Mopar show last summer with my /6 Valiant. It beat a lot of V8's.
