I've been toting a slide-in camper on my 51 1-ton for 20 years. Yes the height of the cab is a problem but easily solved with a couple of 4x4 stickers under the camper. I used the extra foot at the front for a 50 gal. fuel tank. The original 17 gal. won't cut it at 10-11 MPG. The camper in the Arctic Circle photo was a Canadian Vanguard 10.5' and was relatively light but had no head, furnace and water storage was 17 gal. Loaded the outfit weighed 8020 when we left Seattle but added 50 gal of gas later in the day. Tare was 5300, driver off.
The photo of the outift at the truck show is with an C11 Avion. It is quite a bit heavier. At the Cat scale near Red Bluff, CA loaded with half fuel, food, water, driver and passenger it weighed 9080. We had just come over Siskyou Summit headed for LA. Same cab height issue, same solution.