I have a 2000 F150 XLT supercab with a sliding rear and ever since i bought the truck(was bought used) the back glass has leaked when it rains and i've gone through at least 4 tubes of silicone putting it on the outside top of the cab where the cab meets the plastice trim and that dosent fix it so i just keep 2 towels on the top of the back of the back seat and to be honest its getting old and i want to fix it the right way and not with silicone. It seems like the weather stripping is dry rotted from the looks of it. ANY HELP/SUGGESTIONS AT ALL WOULD BE GREATLY APPRECIATED!