Ken,
First let me say I do not have anywhere near the knowledge that you have.

I had a brand new import car 1971 I was constantly resetting the points. I took the distributor out but you could not rebuild it. It turned out the shaft was bent and that would throw off the dwell, when the engine would get shutoff sometimes the dwell was to wide. I would reset the points, start it up, it took awhile to figure it out. New distributor did the trick. If you have an extra one you could try it. Just thinking but that was my problem.

Richard