Orbywan, great job. I really like your rig and your mods. Anything you can do to save gas, even though it's now below $2.00 a gallon is still a great idea.
I have put a Front air dam and wheel skirts on mt 26 ft Fleetwood Flair. Now your design of a "caboose" looks like it would save gas. Maybe paint flames on it! Actually if the paint scheme is continued on the back that would be awesome.
Are you going to put the back up camera on the back? It looks like you need that.
Here is my link to my build.
1993 Fleetwood Flair
Side skirts would be easy if I could find cheap flexible plastic panels to screw on.
I am trying to get a consistent 15 mpg, but I usually drive a little too fast, 60 mph, to get much more than 10.5 mpg. Better "tail feathers" to my rig may be the key.
Cheers, Lee