-There are different strategies when it comes to corrosion protection on the interior surfaces. Skins that are used for an rv like most aircraft are made from ALCAD aluminum, meaning they have a very thin coat of pure aluminum on the top and bottom surface, this provided corrosion protection. Some of the other parts due not contain an ALCAD layer and MUST be primed. After much research, I have decided to use a self etching primer which is a very popular and widely accepted method for interior corrosion protection.