OH, the feet issue!
I lubricated the feet and the finger shield on the lower cover with Krytox [eBay again] and now they slip on and off, lock securely like new and the cover slips in place easily.
Krytox seems to be a good fan lubricant [available as a grease or liquid], discovered this 25+ years ago with a bathroom fan with bushings that started squealing after lubing with quality dino oil in only a day or so, but using Krytox, the fan ran quietly until I sold the house- at a fat profit years later...