[AL in NY]

Sounds like an electrical problem to me. First thing I'd check is the electrical resistance from the distributor points plate to battery ground. Should be 1 ohm or less. If that checks out good, I'd run a wire from the battery ground to the distributor points plate and and run the car with that wire in place to see if your problem goes away. It maybe an intermittent open or high resistance gound somewhere between the battery and the distributor.