for all the DIY's out there, here is a update on our project. hope it may gives others some ideas
as a basis for our truck conversion we will use a '95 Peterbilt 379-119 with a Cummins N14, "Super 10" trans and 250" WB:
this is the FRP box we plan to use:
it's a lo pro morgan (ex Penske) 25' (24'6" inside) x 96" wide x 85" inside height. they can be found for about $2000-2500 (for a nice and clean year 2000 one).
our Pete has a "end of cab to end of rear tire" space of 18' so we have to extend the frame about 7' in the rear.
the Pete is a "Unibilt" (sleeper and cab are bolted together) so after we remove the sleeper we will mount the van box solid to the frame and the cab (we will loose the air cab suspension but this way we dont need to use a flexible rubber boot)
the penske boxes have "rubrails" on the inside and outside. makes it easy to mount kitchen cabinets and other stuff:
we will remove the roll-up door and build a wall with a small door (DMV requirement; to register it as a motorhome in AZ it has to be useless for comercial loading/hauling)
we also plan to do a door on the curb side
here is a (computer generated) pic of how the pete moho conversion should look like when finished: