I still don't see why you guys want to use the same caulk that the manufacturer used and keeps cracking. Just seems like a waste of time to me. I use the 3M 5200 marine caulk on the verticle seams and am very happy with the results from it. I know it costs more but I figure the time saved by not haveing to recaulk because the old caulk failed is worth something to me. I've heard that some people don't use it because it is considered a permanent caulk but that is why I use it. Tom M.