I recently installed the headliner in my '89 740T (it was removed when I purchased it). I understand the vertical adjustments, but mine is not sitting square. The drivers side sits 1/4" inch farther back than the passenger's side. Luckly there is no leaking(yet). When retracting from the vent position I can hear it catch on the rear side, then pop down in place. I'm afraid it will eventually leak and ... well... it doesn't look as nice either. I read the faq, i hope i didn't miss this, but I couldn't find it. Any advice would be appreciated. thanks