I got from Ebay an old Lionel 671 Turbine engine with loose and clunky Lionel precision motor.
After disassembly I discovered, that engine frame has worn 6-32 threads in holes for motor mounting screws.
I'm sharing with you in this topic an idea I came to install this motor back in it's original position.
Goal was not to damage the frame more than it's damaged already and get whole unit back to work. To achieve this I fabricated small brass bushings and put them on 6-32 -1" screws. Screws have been mounted from the bottom of the frame. All has been firmly assembled with self locking nuts.