Driver side window in '93 100CSQ Avant

[David Torrey]

Lowered window in driver's side door yesterday.  Lots of groaning and
dragging sounds.  Window would not go back up.  It's been making a dragging
sound for some time.  I did manage to grab the top edge of glass and
manually pull it up with my hands to close it.  Anyone have experience
repairing one of these units.  Sounds like the lifting mechanism is broken.
Is this a dealer part only?  Taking off the door panel looks like fun, too.

Best Regards
David Torrey

'93 100CSQ Avant  132K miles
'88 Saab 900S  212K miles
'87 Saab 900S  211K miles
'79 BMW 320i   100K miles