I have a 1990 XJ which has an elusive water leak in the cowl area. It causes water to leak into the passenger side floor. The windshield has been replaced and thoroughly checked to be absolutely sure that it is not the source of the leak. The fan box has likewise been eliminated as the culprit. This leaves the cowl. When water is poured on the cowl area, it eventually shows up in the floorboard. I currently have the carpeting removed, and the front fenders off the vehicle. There is a pinch weld where the cowl and the inner fender are joined at the top. This pinch weld is covered with seam sealer from the factory, but it has dried out over time. I intend to remove the old sealer and apply it fresh. The location of this seam is just below where the antenna comes up through the fender. The top of the cowl on the right side of the vehicle is a solid piece of metal (no access to the cowl innards from the top). Does anyone know if the seam I refer to is the likely source of the leak? I am tempted to cut an access hole in the top cowl metal to gain access to it's interior but that would be useless if there are no sealable seams in there. Also, is it it a good idea to use spray undercoating/rustproofing chemical through a long wand to coat the inside of the cowl? Any advice appreciated. Sorry for the long post. Thanks in advance.