So I got over those chumps. I found this:
Truck Fuel Saving, Aerodynamic Fairing, Aerodynamic Parts, Truck Industry
The lower edge of my motorhome is nowhere near as tall as a trailer. Plus I don't need the movable access as presented. What I could use is the lower flexible rubber parts which I could attach to the bottom edge of the body between the front and rear wheels. I'm going to give them a call and beg.
Now if I can get the front air dam made up to channel air around to the outside of the motorhome rather than underneath and against the front tires I'll have a good start.