Headlights problems of the 1997 Ford F-250

1997 Ford F-250ld rear window leaks. You guys have already looked into the problem but I think it really needs to be taken care of. I and many others that I have talked to with the sliding rear window have had this problem and it is destroying the head lights in these trucks plus other damage to the truck and what's in it. This happens anytime it rains hard or soft and when I wash the truck. I have a friend that works as a mechanic for Ford and he said he has seen a lot of these problems. Ford does not really have a good answer for the problem and when they do fix it, it does not last for long. I have no problem with Ford trucks and would buy them again and I think that they need to find how to fix the problem and fix all the trucks that have this problems. Thank you for any help.