Take out the windows
, vents and anything else that is attached to the body. Here's why:
1. There already is a sealant of some sort between the frames and the fiberglass. This will make a boundary that the Interlux (or any other paint) may not like and can result in peeling. Remocving everything, painting
and then sealing will provide a better and longer lasting paint
2. As you just bought the trailer, there is a good chance that the windows
and other openings haven't been resealed in years, meaning it's time to do it again. BTW: We never use silicone type sealants on FGRV's. You want to get RV Butyl sealing tape from you local RV dealer or on-line.
3. If there is already all kinds of sealing goop piled on, this will give you the opportunity to remove all of it.