Really weird ignition issue...

Yeah!
while all help is appreciated, he sure went to the moon and back on that one.
This may have come down to rotor phasing as stated by @1WildRT .
I compared these two. First is the one in the car.

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I set the reluctor gap back when I installed this distributor. This is the #6 firing position.

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I spun it around to #1 and put the rotor on.

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Then marked the rotor tip position on the distributor body. Look at the difference between the two. The left one is one from the shed. Right side is from the car.

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There is 1/4ā€ difference in rotation between the two. I could probably figure out the degrees that is with some measurements and math but here are the pictures.

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The right distributor was 1 1/2 from that housing screw to the right. The left distributor was 1 1/4ā€. When I moved the rotor on the left to match that 1 1/2ā€ number, here is the reluctor wheel.

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I’m going to stab in this distributor and report back.
Not sure what you did there. There is only one way I know of to determine phasing. That is to use a timing light and preferably a simple one with no "dial up" feature, and determine when the spark actually happens in relation to the rotor. You need to cut/ drill an old cap so you can see the rotor and mark the position of the no1 tower, then spin it either in engine or with a drill, firing an ignition system. The timing light will flash at the point the spark fires, and the light will "stop" the photo in your brain of the rotor passing the cap tower