This is a "Hidden Hitch" (brand) that is rated at 5000 pounds or 6,000 while using a weight distribution system. It will work with any frame width from 30 - 46", so might also work on trailer frames as well as your motorhome.
RV hitch - 31" to 46" frame widthThey have other models, you can search for them. This is the one I was considering for my 2002 E-450 chassis. But I may still have a custom hitch built. Like you, I have a very short chassis extension, my overall length is only 23'.
I can attach to the Ford frame, and do anything I want if I attach there. Then run a 12" long 2" receiver holder back to the bumper (so it will not stick out or be way under the bumper). My plan includes 3/16" thick flat stock to hold a 3" OD cross member, and 2.5" OD (2" ID) bar going back to the bumper. I know a certified welder, and he can built it for me. I have a 22,000 GCVWR, and the V10 engine with 4.63:1 rear axle ratio. My GVW is only around 8,000 pounds or 9,000 ready to go camping, so I am also a lot lighter. My plan includes a 10,000 pound trailer and 1,200 pounds of hitch weight. The E-450 that I have has a rear mounted wheelchair lift, and 12 seats.
Good luck on your project.
Fred.
