78_f800 thanks for the insight on how to repair the seam sealer. However, my 78 crew's seam sealer was in excellent shape in the drip rail, no cracks, etc and mine was still rusted out mid way back (directly between the doors) on the roof panel that comes down to the drip rail. No way road salt was the issue, must be condensation then. Anyway, i ended up cutting out a section about 1" tall and 10" long of that roof panel and replaced with new metal.
1996 F150 4x4, 351, auto, LB, K&N Filtercharger, "Silver Bullet"
1978 F250 Crewcab 4x4 "in the works" .....finished 6 years later!