When I had my Granville i had no cab air either. Way too expensive to fix! So I mounted a Honda 2000i on the rear extended bumper and ran the electrical cord down the side of the RV to the generator. The Honda ran my coach AC perfectly while driving down the road and the coach AC cooled down the cab Perfectly! I mounted the generator in two heavy duty milk crates that were bolted to the bumper. In my case the bumper was reinforced to the frame!
