Ok....after one hell of a fight, the gas tank is back in. Not surprisingly, it still doesn't start using the key. It does fire right up jumping the starter terminals though and seems to run fine, which is what I was hoping for. I'll wire up a simple switch directly to the starter, finish the rest of what I need to get done to make ECR, and come back to the switch troubleshooting as time permits.

Many thanks to everyone for all the advice and reference data...I really appreciate it.