Heres is a probably little known fact. Those little plastic spacers are used in more than just the S/C. I had never had any trouble with mine........was trying to figure out what all the talk was about them.
This summer the window wouldn't go up on my 1987 Bronco. The motor ran, but the window just hopped up and down.....tore it down, voila plastic spacers in a million little shavings.
Tore down a spare S/C window motor I had. Although the housing, motor and gear pitch was different, the spacers were exacty the same.
I'll bet any Ford power window motor would be a good donor for these. In fact , the power tailgate window was having some issues, so I tore it down tonight and fixed all the problems. While I was at it, I overhauled the electric motor.....Bronco power tailgate window motors also have these plastic spacers in them.