I suspect you're going to have to make some important decisions. I bet you can get the truck registered as a motorhome or rv (different states call them different things). But, pretty sure you can't use an rv or motorhome for commercial use. Now, you certainly can claim you're not commercial. But, if you run into a commercial vehicle inspector in the mood to do some enforcement you might have a hard go of it. The federal commercial vehicle laws basically say something like "in furtherance of a commercial venture." So, if you've got a sticker on your race car for "Acme Mufflers" you're now commercial. Even if there are no stickers on the outside of the rig. All they have to do is go to the races and wander around the paddock and make some notes. Then when you pull out onto the road they can nab you. Anything over 10k lbs. combined (truck and trailer) weight means you have to now follow all the commercial vehicle laws. I know, "there's all kinds of people at the race track doing this." Yep, there sure are. And every once in awhile the cops write some tags. Guessing you don't want a lecture from me so I'll stop now. There are a lot of people using HDT's (heavy duty trucks) to pull their camper trailers. Most register their tractors as motorhomes or rv's. Doing so has some distinct advantages for campers. There's tons of information here: HDT - Escapees Discussion Forum
The Heavy Haulers Resource Guide is probably where you'll want to start reading. Good luck.
'03 Freightliner FL112, 295" wheel base, with '03 United Specialties 26' living quarters, single screw, Cat C12 430 h/p 1650 torque, Eaton 10speed , 3.42 rear axle ratio