Thanks Road Fan
I was about to post how I fixed the squeal and you described it exactly - the drive wheel had tightened against the bushing.
It took me a little while to figure out how the end play was adjusted as you can tighten the wheel against the bushing, locking it solid to the body. After trying it a few different ways I realized the threaded drive wheel just tightens against the lock nut -pretty basic. I adjusted the end float to about a 1/16th of play, hopefully this isn't too much movement for the windings.
It hums along nicely now, another vintage part saved from the landfill.
Thanks again,
Good fun!