I’m adding power windows to my Caprice and when I removed the rear panels I found something strange. The car is very original and I was wondering if anyone has seen something like this before?

 

I worked at a Pontiac Dealer in the 80's. WE had to attach the tag to the RO to prove we went in there to do a glass adjustment or other type of repair. The factory rep did not always check but when he did....

 

Thanks for the info.