Don4331 hit upon the Open Dirty Secret from back in the era that slide in pickup campers were mainstream RVs . All the F -250 Camper Specials and C-20 Camper Specials in the real world were overweight, especially on the real axles .
But back in the day " trucks under 1 ton" were rarely weighed , or subject to " No Trucks " restrictions , at least in the US .
And Camper Spec 3/4 tons held up to the abuse reasonably well , at least for occasional camping/ vacation use .
The F-350 Super Camper Special , and GM C-30 Dually actually could be within ratings , but by that point new sales of Slide Ins were waining , and Fifth Wheels were the big growth item in RV's .
I'm not sure the trucks were overweight on rear GAWR but they were overweight on GVWR.
In my collect of stupid stuff, I have a brochure from Ford back in Rusty's era, and there was some "creative" marketing.
F-250 is listed as having a. max payload of 2,640 lbs and b. max GVWR of 8,200 lbs. But the base truck weighs 6,400 lbs - that math doesn't add up. (8,200 - 6,400 = 1,800), so ~3/4 ton was max payload: less if it had 460, auto, a/c, etc, etc. Rear GAWR was 5,300 lbs, so you shouldn't have been exceeding that even with overhang. (Current F-250 has 9,900 lb GVWR and payload + empty weight
are less than GVWR)
Similarly F-350 Dually had max GVWR of 9,900 lbs* and scaled 6,800 lbs, so math says the 4,770 lb payload was calculus or some other creative mathematics. (Similarly current F-350 dually has GVWR of 14k lbs.)
I put the leaving out of the standard battery, standard propane as an Open Dirty Secret in the RV industry. ,You can sure sell a lot more trailer for the the extra ~100 lbs on battery/propane on tongue. Yet it rarely prevents you from physically towing the trailer.
What you need is updated version of born free camper:
*Staying under 10k lbs GVWR eliminates any concerns on whether CDL is required.