RV Armor is a 5000 dollar or more improvement. I had one put on. It's a nice roof. I had the help of an insurance claim though. Dragged a tree branch across my roof and tore it up some. A new membrane would have been 11,000 or more according to the dealer. After that quote from the dealer the insurance was happy to take my offer to accept the RV Armor roof. Anyway, as with anything prep is the most important step to redoing the Dicor self-leveling sealant. Thats what is recommended. Clean the area with mineral spirits and remove any that is even the slightest bit loose. A heat gun/hair dryer makes removal of the old Dicor easier.