Back to the drawing board.
Got a reply through the dealer regarding mounting ANYTHING on their 4 inch POC bumper. NO WAY. They don't even recommend the spare tire carrier the thing ships with. No bike rack etc.
As to a FRAME mounted hitch for the cargo carrier like:
Adjustable Width Trailer Hitch Receiver for RVs, 22" to 72" Wide Curt Specialty Trailer Hitches 13703
They "Don't recommend anything fastened to their Ultra-Lite Frames" and doing so will void any warranty.
Looking at putting the darn thing on the front truck mount reciever and mounting and dismounting the entire thing at the campground.
Leaving it in the truck bed. Most likely that will be the final solution.
Now to see what I can do with the cargo carrier and bumper hitch I bought. Ebay?
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW