Hi Mark, I walked back through the "power on" diagram carefully with another electrician-trouble-shooter. He was excited about helping to solve this problem, but was as frustrated as I am after 4 hours on Saturday.
For sure, there are no bent pins and I'm testing only the wires on the "power on" diagram.
What stumped him is exactly what is stumping me: how could it possibly be that I have 12v coming into the sscb, but only between 5v and 5.5v coming into the yellow wire that goes to the ignition switch? The sscb is the only thing in between those two plugs and I just replaced it with a new one.
Another thing we learned: While jumping 12v to the red/black wire at the ignition plug, we measured the power coming to the "B" position wire on the ignition plug - the one that power feeds to after being passed through the kill switch, headlights, and a splice. As soon as we put the tester on the "B" wire, the volts measured decreased over a couple seconds down to nothing. What could that mean? It threw me off badly.
One thing that the latest helper told me that I did wrong was to plug the new sscb into sscb1 while the battery was plugged in. He said that I may have fried the sscb. But, he took apart the old sscb and couldn't find any place on the circuit board that looked bad, burnt, or disconnected.
I've double + checked everything and still have a large paperweight in the garage. Any other thoughts or any shops in Wisconsin that you know of that can help me would be appreciated. I live in Franksville (53126), but go west of Madison often.
Thanks for not giving up, Mark.