IMHO, silicone doesn't belong on a boat or a motorhome. It doesn't stick very well under the best conditions, and it takes a lot of labour to get rid of it when you have a leak and need to seal it properly. Any good marine caulking, like Sikaflex 291 or 3M 4200 will do a far better job initially, and will last for years without discoloration.
I was reminded of this when cleaning the top of my Girard awning cover, where I found some PO had dumped a couple of tubes of clear silicone at the joint between awning and coach. As I was pulling it off, I was getting wet from all the water under the silicone. It was a dry day, so the top of it was bone dry. There wasn't any water getting in, so the silicone was unnecessary in that location, just a PITA.