Silicone Remover and ThreeBond 1207B
Recently, I had to remove silicone from some engine gasket surfaces and tried for the first time Permatex Silicone Stripper Gasket Remover. Silicone can be stubborn to remove and this gasket remover made the job a bunch easier. I found it at my local auto parts store.
When choosing a liquid gasket, I have had good success with ThreeBond 1207B. I purchase it from a BMW dealership.