I contacted him by email and it was like he never heard of it ...then finally after several tries said it' s a factory modification.I won't bother him again.
Don told me he had a special order request once for a single cab-over bed, and he worked it out with the factory. I guess that is what he meant by "It's a factory modification".
Maybe he thought you were asking him to modify a unit you already had. I can't imagine doing a conversion after the fact. The cab's roof is cut out during construction for easy pass through. Reconstructing an existing PC for a cab-over bed would require a lot of messing around, but easy to accomodate during the birth of the RV.