You don't need to clean your base in order to change the wax type. You waxed, and then rode. That's good enough. If you REALLY want to clean it though, use a citrus based cleaner of some kind, not rubbing alcohol. As for the 4WD, I've used the warm, cold and all temp. It's not bad wax. OBJ in general makes decent wax. There are cheaper alternatives though that work just as well. In the end, it's just wax. Don't overthink it.