Over countless years of working on cars and now rvs, I've found virtually not much of anything will do a good job of removing silicone caulk except for two things: gasoline and Mechanica Silicone Caulk Remover. I know, gasoline is a smelly flammable material but it works and it's relatively cheap and accessible. Just wet a rag with it and place it on the silicone for a few minutes and it will start to crumble into little pieces and eventually the area cleans up well. The Mechanica is sold at Ace Hardware and works well but is slow and messy
