Thanks Julian ~
By small window I'm assuming you mean rear window -?-
On my car (1964) it has a fixed 'post' on the bottom which slides down into the frame/door. On the top part there is a a single hinge held in place by a rivet
If I cut the weatherstripping halfway through in these 2 places, I'm thinking the seal would be able to be installed w/out removing window, frame, etc.
I could repair the cut w/superglue.
Again, thanks for your reply. ~ Mark