The use of a silicone based sealant didnt work ,the first attempt failed after 5 months and over time had rust forming .I sanded all the areas ,treated the rust ,reprimered and painted and sealed it with a 3m DUCT TAPE.No water around the seam to regrow the rust and looks ok for a beater car. I was going to look into the gasket set but since I wasnt interested in its function I went with this instead.The next owner can fiddle with it if he or she wishes .Im just glad the water leak is gone and the rust worries or behind me for now.Most of the 3m tape products come in several colors at the big box lumer yards for those who somewhat want to match the color of the car ,my car is black so its somewhat the best color to match in this case.If you do the silicone it will become an issue like mine was ,the windshield is another area you dont want a silicone based product involved , time with rust has to be caught quickly or the repair becomes sometimes economically unfixable depending on area and size affected.Summers in Texas are pretty hot so Im sure it will be ready for replacement in a year or 2 but it will be obvious to its failure and not hiding rust forming.