that is a small Class 'C', the body is molded fiberglass and it appears the roof is too, I think that model was sold as weekend party van to be in competition with the custom van craze at the time
those rounded 'caps' at all the corners and edges, cover where the body and roof sections all come together
scrub/clean all 'mating' edges and nearby surface clean it it 5 to 6 inches wide
first with water, then with a rag and acetone
you want the clean area wider than the Eternabond tape, clean 3" each side of centerline of the mating edge wear the molding caps overlap the roof, 3" on the molding, 3" on the roof
use 4" wide EB tape. it comes in 50 ft rolls, you need at least one roll and might need more
good luck
here are bubble top camper vans, the steel van body is intact, only the roof is added on,
