I finally got around to tearing into my problem.
It was the clutch pivot bearings that were rusted up. I had to remove the covers and heated the shafts with a rosebud. That didn’t do it, so I poured EvapoRust on top of them 6 days in a row and every day they would move a little more until they freed up completely. That stuff works!
It sure beats having to take off the transmission cover to access them.