The front bumper is a GMC Motorhome bumper. The windshield looks very much like a GMC motorhome windshield. The window behind the windshield is a GMC motorhome window, as is the next window back. From there back it is an Airstream trailer as far as I can see, other than the dual front to back rear tires, which again look like a GMC rear end.
If it has front wheel drive, it has to be a GMC marriage with an Airstream. The Diesel however throws me, as it has been really hard to substitute engines in the GMC design, as the front wheel driveshaft goes through the oil pan on the original engines.
I had a GMC motorhome for several years, and was just comparing the photos of it with the rig you show.
And I am sorry, it has neither the grace of a GMC motorhome or an Airstream trailer. But interesting anyway.