Peter,
The stuck regulator/motor was what I started with. Mine was right, front. Power from the switch to the four-wire connector and I could hear a clicking at the motor. It turned out the two exterior gears were bound at their extended range. Once separated, the tension released, I applied battery power and it operated. I made the mistake of re-installing w/o taking the time to investigate deeper. Put it all back together, lasted a day or so then stopped again. Practice session paid off because I tore it apart much quicker (typical) and this time spent the extra time that I should have the first time. Glad I didn't buy the used assembly since this one is now working great. Actually, the smoothest operating one of the four.

Keep us posted . . .
Steve

__________________
Steve
'87 300TD - 132K - Soon 4-Sale
'84 300D Turbo - 122K - Driving
'77 VW Type II - 77K - Restored
'08 250EX Ninja
English Bulldog (Brier) - My best friend. Passed away 12/02/04 while in my arms.