I managed to post this in the wrong thread the other day somehow but thanks to Oceanbrave’s comment on the other post (or else I wouldn’t have noticed! Thanks for the heads up!)…I’m adding here for visibility for future folks searching for this same issue.

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Well, I feel like an absolute idiot, but I got it fixed. There was a break in the black wire for pin “A” per the diagram shown further up the thread. The wire jacket looked fine. But given that it was such a thin gauge wire, it must have broken all of the strands and stretched so they wouldn’t touch.

So all in all, it was the typical issue that everybody else has been experiencing just very well hidden.

Thanks to everybody for your patience and help throughout this!

 

Oh and as an update to the first post on the thread…it turns out that the alternator and radio going out at the same time as the shift interlock just happened to be pure coincidence. I added that in the first post due my thought of the cause being an Occam‘s Razor theory approach, but it turns out it was three different problems at the same time. But I guess that’s why we enjoy fixing our own stuff…the thrill of solving the problem!