Traditionally, they are made with a wood frame, filled with styrofoam, covered with aluminum sheetmetal inside and out. I don't know if your Sunlite is made that way.
When soaked full of water, they tend to be heavy. On the old Palomino that I helped to work on, you needed at least 4 people to lift and transport the roof.
If you have the scissor type lift, beware of the preloaded torsion spring inside the upper tube. The spring is held by the brackets at the rear of the roof, which tend to become unaligned from the permanent torsion when the rear wood beam has rotted enough.