I am restoring my dad's '66 911. It hasn't been driven in over 20 years. Had the engine rebuilt recently. Sounds great. Anyhow, the passenger window will not roll down for some reason. Upon opening the door panel, I found a spring laying in the bottom channel. Not too sure where it came from or where it goes. Has anyone come across this problem?

 

Yes, but you probably want to ask this in another forum.

There's a big 'clock spring' around the window crank. If that's what you found insid the door, you likely need a new regulator and new window channels, as the glass is probably 'cocked' in the frame.

 

There should also be a “pin” that held the spring on the regulator, that was also the axel for one of the arms, in there somewhere. A pretty hefty pin. It was not uncommon for the pin to split/shear or pull out dropping the spring killing the regulator in the process.
https://europortparts.com/sku/911542...SABEgI5BvD_BwE