Got to looking at your problem again and one thing doesn’t make sense to me. You said that you’re getting 12v on IGN1 while in run. You also said you’re not getting 12v on IGN2 in start. But you connected the two together and the engine cranks in run. So that implies that IGN2 and SOL are shorted together in run, but not in start like they’re supposed to be. I’m not sure how that can happen but it has to be a problem with the ignition switch.

It just occurred to me that you said you weren’t getting 12v when starting so my diagram is wrong. It says to connect the diode to IGN2 OR SOL. It would have to be connected to SOL to work since IGN2 is dead. Sorry about that.