thanks for the tips guys, i guess my question would be this. i know people do it all the time, but is it neccesary to use the oven/heatgun to get rid of the old sealent completely? or is it ok just make sure that that a put a nice thick seal on top of that all around the edges, because for the most part the seal is ok, but obviously there are some gaps that need taken care of. So Sealant on top of sealant ok? thanks