My dome light lens on my '95 XLT began falling out a few weeks ago. I would invariably find it on the floor of my back seat area and would re-install it by pushing the four teeth into the slots on the fixture. A couple of days later it would drop out again. It looks to be the original lens since it is yellowing as a function of age. The last time I put it back in the fixture the lens cracked. I've ordered a new one from LMC but I am wondering why a lens would suddenly begin falling out after two and a half years of my ownership and twenty three years of previous ownership. Is there some secret to installing these things?