Hi all. Some of you may have read my intro, some haven't. Ok my purchase of a 1989 Gulfstream RV has been a long while in the mind set. Now that I have done it I need some guidance please. There are wet spots on the interior ceiling. I have been on top and there is water pooling around the roof vents. The 'sealant is hard and cracked. Is there a preferred way of removing it to reseal?