Depending on your tongue weight. I would weld another receiver section below yours. Then use a stinger. I think super hitches are a little over priced for what they are.
My old crew cab had a dual slide out bumper to get past the 11' camper. Worked great, heavy but worked great.
Make sure you have the support at the truck you need. I built one for my bobbed toy (so I could haul normal length stuff).
I ran the female portion all the way to the cab so it is attached to multiple cross members (works great).
The pup trailers are a good example if you are looking for examples of extreme length extensions.