Intermittent crank no start

Yet another idea: Do you have a workable breaker points distributor lying around. The coil/ ballast wiring for breaker points is same for electronic. All you need to do to swap in a points dist. is.........

Disconnect the ECU box
Drop in points dist. Connect dist wire to coil NEG in place of wire now connected
Unfortunately I don't have a points distributor around.

I'm going to start by checking both functional paths for voltage drops and go from there.

Then I'll try some of your other suggestions.

I really appreciate the detailed instructions, this is just what I needed. I'll keep you updated.