The trim, gasket and windscreen are installed as a "one piece" unit.

The gasket is placed around the windscreen, the trim is inserted into the gasket and the entire assembly is "roped" into the aperture. No way, or at least I have never seen anyone do it successfully, to insert the trim into the installed windscreen.

Your thinking is correct. The trim acts as a lock to secure the glass into position.

You MIGHT get lucky and be able to remove the glass by CAREFULLY feeding the lip of the gasket over the body from the inside using a plastic trim tool but I doubt it.

More than likely you will end up replacing the gasket. I suggest, if you have never done this job before, taking it to a glass shop and have them do it. The windscreens on coupes are one of a kind and tend to be pricey. Replacing a broken one is a major expense.

Even worse news. By removing the trim you have probably bent it.

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