Is the roof of the 86 scamp 16 foot strong enough for roof air?
Not if it was not built that way at the factory. Check over in the YAHOO group SCAMPERS for threads on this subject. Several discussions and suggestions - none very quick, cheap or simple but suggestions nevertheless.
I think the roof had to be reinforced when original unit was ordered.If it does not have a AC now,then i think i would say no.
We had the same problem with our 1979 17' Boler. We bought a portable air conditioner with a single hose (Delogni). We vented the hose and drain through the floor and solved the problem for arround $250.