WHAT could this be?!?

1968 barracuda notch
1973 440 motor

at random times my car stalls from either not being warm or stalls because it use to have bad timing or carb tune.

anyways...

So not always but at random times rarely - the car wont turn over.
(wait it out and then it turns over and on)
i recently replaced the starter with the mini starter (GREATNESS) but something else seems to be failing at times... bad wire? bad ballast? a solenoid? regulator? hmmm
recently also replaced the positive battery cable

IDEAS?