[saturn914]

Nope. Not reverve Threads. But I have now made it twice as bad.
I unscrewed the ome from the other motor to check the threading. When the screw came out, the Headlight motor fired up and opened the headlamp unit and then closed. ( The ignition was off and there was no power other than passive power from the battery.)
Haynes manual has no reference to this happening.
I think I triggered a 'manual opening control thingy' and have no idea what to do.
The lights still open and close & work perfectly but what the?
I hate having left over parts that I know were put there for a reason.
Baffled!