Fried ECM

Thanks to all for the tremendous amount of help received yesterday. My plan for today is to finish unraveling fifty years of electrical tape and expose every wire and connection in the engine compartment. Then one by one inspect clean and check resistance and voltage for each. Once this is done I will move to the other side of the bulk head connector and do the same. I noticed the starter relay to starter wires are fifty years old and are not in the greatest shape, so those will be replaced but not until the problem is found. Also I will get a new ing. switch from NAPA to replace the auto zone switch. (which I do not have much faith in) again not until the problem is found. Thanks again to all who have been kind enough to lend assistance.

It's hard to know what you'll find until you look. My current car came from the desert - a lot of dried out insulation etc in the engine compartments hottest locations etc. Under the dash and inside is still pretty good. I installed a replacement engine harness and after 20 years or so, some terminal connections were failing and I've had to replace them.

One possibility to look out for on the ignition switch is its for a different year/model.
They shouldn't physically interchange but maybe they can????
From 68 to 69 Abodies the Ignition 2, Accessory, and Start wires connect to different switch terminals.

Why do 68 & 69 dart iginition switches have different # ground plug ins?
[SOLD] - nos mopar ignition switch