I did it somewhat successfully- at least I didn't break the glass and eventually stopped the leak. But if you look carefully on mine, the trim is lifted off the rubber on the bottom edge. I would cut the seal wherever possible , perhaps in several places. Do not pull on the trim any more than is absolutely necessary. The glass is very thin and getting the gasket on it while it is off the car is like working on a time bomb because the gasket must be stretched so much and the glass is curved. It goes on in theory like any other old-style glass , pulling string from around the inside lip of the gasket from the inside while a helper pushes on the assembly from the outside. I only did it because no shop would guarantee they would not break the glass ( I understand now) and I wanted to be sure that I could fix any rust in the channel myself.

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)