BTW here is the best tip I ever got outside of being a cab
driver:

If you have a screw that has the top worn off and
you can't get it out with a screwdriver do not try to
drill it out first. A method that was passed on to me
was to file one of the screw sides flat and then the
opposite side. This makes it a snap to get the screw
loose and removed with a small pliers or other pinch
tool.

I encountered the initial problem with a 5.25 drive
and couldn't sensibly drill in toward the mechanism.

It's the best tip I know and I wouldn't have thought
of it yet if somebody at alt.fifty-plus.friends didn't
tell me about it. Save and share with my compliments.