Ok the layers explanation helps
Did you bend the channel slightly around the edge where the stationary glass ends in the middle and press the channel against the flange in the body?


1949 Chevrolet 3100 Suburban Carryall
"Bad Guy"
In the Stovebolt Gallery
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1950 Chevrolet 3100 3-Window
In the Stovebolt Gallery
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1966 GMC Suburban Carryall Custom
"Big Guy"
In the Stovebolt Gallery
More pix on Photobucket