[RustyPile]

This is probably why you're having problems with the seals.. That piece that broke off helps guide the window up and down in the channel. This not necessarily indicative of a bad regulator.. The channel rubber gets hard and pieces break away.. This causes that piece to dig into the channel. Given enough time and forceful cranking on the window handle, it will break off..

I'm not saying this as brag but I disassembled all the pieces, division bar, vent window, channels, lock mechanism and regulators when I redid mine. It's not that hard. I think you can clean up that broken piece, remove the glass from the carrier channel (part that's attached to bottom of window).. Disassembly is well documented in the service manual.. I would imagine there's some how to videos posted on U Tube.. Clean the area where that broken piece attaches.. Align the two pieces carefully using the old remaining marks.. Spot weld the pieces back together...

This is not rocket science, you can do it.. Work carefully and check yourself after each step......