I used the rope method- just be gentle and take your time. I measured the center point of the body and marked it with a grease pencil and did the same for the glass.

Start at the bottom having a helper push. Sealant is generally a bad thing. A new seal will seal. Sealant can trap water and creat rust. I would not use RTV, because when it cures it creates acid, and hence rust.

My wife just put her weight against the glass, I pulled a little, then checked for progress on centering, height etc.. Push and pulled a little, then continued. Once the bottom is done, it's not going to move much.
In mine, it did dribble water for about the first week- then we had some warm days, and the seal settled into place.

It's rewarding when it's done. Can't believe I ever paid someone $50-100 when it is easy. I was always parinoid about breaking the glass.
Front is more difficult, because you fight the dash and trim stuff more. Back window is cake!!

Michael

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Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E