The starter operated intermittently. Seemed like obvious brush problem. Looks like the original starter had never been replaced. Absolutely could not get top mounting bolt loose. Used long extension and breaker bar. I even bought an impact wrench (any excuse to buy a new tool)but couldn't budge it. Aha, the solution! I drilled a hole in the bottom of the front cover and sprayed the whole area where the brushes are with tuner cleaner. So far it's been starting every time.
P.S. Unfortunately, two days later, a significant noise developed in the engine.
Sounds like a rod. This may be the end after only 200k plus miles.
Definitely good news/bad news
Papa Al