The GEM that I got with the 60mm over 20 years ago has had it first overhaul as it was, like me, getting a bit stiff with age
A good clean and regrease, and its working nicely. Then I decided to add an RA drive using the spare EQ5 DEC motor I have. The result is shown below. Not as agricultural as the original effort and considerably lighter. Just tested it over 1 hour with the EQ5 hand controller and it looks to be very close in speed.
( Let it run for 3 hours, spot on the marks, looks like the gearing is the same as an EQ5
)
Bill