Here's my Cummins long dog. The spaces in the front and rear of rear wheels is for some aluminum steps that I've not yet installed.
This was a cube body delivery truck. I just stretched this bed to fit. The guys at home depot just shake their heads when I throw 10' drywall in there with room to spare.

truck box done 001.jpgtruck 001.jpg
"use it 'till it breaks, replace as needed"