Off the top of my head, the ignition wire at the relay is jut to bypass the ballast resistor when cranking. Unless it shorts out somewhere I don't see it causing a stall situation.
Assuming the problem persists after changing the ECU and coil, I'd be suspect of the pickup coil in the distributor.
Of course 50 year old wires are always suspect.
Agreed, and the ballast is bypassed in the start position so that eliminates it.
I would check the see if you're are getting spark when the problem occurs. If not, verify grounds even if you've already done so. I have in th epast run a small braided ground strap between the ECU and engine block making sure both surfaces are clean of paint etc.
Using a brass or non magnetic feeler gauge, check the reluctor gap to pick up coil, should be .008-.010" .
usually a good idea to check it in a couple of places. Then try the pickup coil.
Keep us posted
