Un-hacking ignition wiring

Swingin73Dart said

I really couldn’t say where that connector is supposed to be, that part of my harness is off my parts car as it still had the factory ignition intact. And I just stripped everything off the car and sent it packing. I think my 73 factory manual has a simplified ignition schematic I can use.

View attachment 1715471829

If this is right I should be able to run all these wires direct from the module and eliminate that plug entirely using the factory harness

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That's right. There are fewer and fewer 'actual' 5 pin modules which require a 4 pin resistor. Most any module you run into anymore, unless it's an old one, are 4 pin, which can use a 2 pin resistor. If you can mock it up to run, and leave the resistor feeding back to the module disconnected, you'll know for sure. Otherwise you can check resistance between the resistor feed to the module and the other pins. If they are all open, it's a 4 pin module. The module MUST be grounded to run.

Also, the half dual resistor going to the coil is really the same as the old points system. That is, ign1 feeds the resistor and that feeds the coil. The IGN2 hooks to the resistor on the coil side, and that is "hot" during cranking. This feeds "hot" battery voltage to the coil directly during start, and BACK feeds power through the resistor and back around to the module for starting.

What I mentioned earlier, "IGN 1" shown in your simple diagram, is another problem. The path for that originally was the big red battery feed---through the bulkhead---to the under dash welded splice---to the ignition switch---back out the bulkhead on ign1---each terminal point is a voltage drop potential. That point also feeds the alternator field and VR ign. If that point suffers voltage drop, it will cause an OVER charge condition. That is the circuit you should consider adding a relay.