Hi Chris, In answer to your question, 'yes' it is a simple answer of removing the old sealant and replace with new. There best way I have found to remove the old sealant is to use a Stanley knife, you then use a 'sealant remover' from B & Q or somewhere similar just to clean off any remaining sealant. Most DIY shops sell it. You must make sure that all of the old sealant is removed or it could cause problems when putting the new sealant on. Concerning the new sealant, DONOT go for the cheapest, basically the more you pay, the better the quality, and the longer it will last. Make sure that