It won't move that much, a little, maybe a mm or two. There are four torx head screws holding the rear glass to the rear mechanism. You should be able to see them from the inside just above the tracks. If you can crank it so it goes up, much easier but I don't think you have to. There are six holding the front glass to the front mechanism, same screws.

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'05 E53 3.0 6mt
'17 F30 340ix 6mt
'96 E36 328is, in progress