FIGURED IT OUT!
The AUTO/OFF/MANUAL switch was failing. Some De-Oxit in there made it work fine...
Then the connection for power at the starter was loose. The solenoid was working, but the wire from the solenoid to the starter was loose at the starter location.
It's all fixed and working great now!
Thanks for your help!
I used to use (and still do - left over cans after I retired) an old product from Caig Laboratories called Cramolin. It's basically the same as De-Oxit according to what folks tell me. I did find that when I used it to get rid of corrosion I had to flush away what it lifted off the contacts a few days later and apply a little more for the long term. You might want to flush out the switch with a degreasing cleaner in a week or two and then spray a little more De-Oxit in there.