This might be a stupid question, but once a rear window is removed, can the same one go back in?
The new van came with a double glazed window that used to be fitted, but was never put back when the previous owner got a new rear door. The double glazed window appears a bit warped, so am not 100% it would fit snug, am hoping it will straighten out once fitted
If not, would have to put the old one back.
Is the above worth a try, best left alone.