No reason you can't except the placement of the roof ribs. If you can get between the spars, it shouldn't be any more difficult than putting in a Fantastic Fan. I wouldn't want to cut a rib unless I could do some aluminum framing to reinforce the structure...just like cutting a rafter.

The PROBLEM however is probably going to be finding a skylight with the correct curve to match our roof arch. Most all new coaches have flat roofs.