89 911 Cab - vent window - how do I replace the rubber cap seal?

[ajmarton]

I have an 89 Cab and want to replace the Vent Window Cap / Corner Seal
(911-542-065-41-M260) - its the little rubber piece that the window comes up against when you bring it all the way up. There are 2 screws on top and apparently it takes 2 rivets as well. My question is how do I remove the fuzzy channel (guides window) that is against the vent window? Do I pull it out or do I have to dis-assemble some portion of the door.

I am also trying to replace the rear seat belts and can't get the bots to budge. Any suggestions? I tried some penetrating oil but that has not worked.

TIA...