I have not fiddled with those windows for years, so my memory may be failing me. But here goes.....
Glass - gasket - trim - install
put glass in gasket
put trim in gasket
put assembly in car using lubricant -
Place the bottom corner into the opening first,
then slowly work both vertical gasket edges upward, always paying attention to the corners.
I don't remember this as being at all difficult.
It is true you cannot install the trim once the window is in place, but likewise you cannot install the glass with the trim in place. I'm thinking this may be your problem?
Or... the vendor sold you a typical "just like the original" that in actuality isn't "just like the original".
Good luck,
Larry
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