Geoff, I am not a PU camper, but during my winter stay in AZ and CA, I see several spending the winter months in their PU Campers. Don't get discouraged.
Done it, lived in one from May 2008 to August 2009. My advice is thus:
Have good exhaust fans and vent covers on every roof vent.
100lb Propane tank is a must.
Extra insulation is a plus. The little Damp Rid pouches that are meant for going in suitcases for storage are a godsend for keeping moisture down amongst clothes tucked on shelves near the roof in the cabover or in any other spot that doesn't get regular air circulation.
Follow along with me at The Journey of the Redneck Express CBChannel 17Redneck Express '1992Dodge W-250 Power Wagon - Club Cab Long Bed V8 5.9L 4spd H.D Auto 4x4 4.10 Gears '1974KIT Kamper 1106 - 11' Slide-in '1987Pullman Mini Camper
Nothing to it. I lived in my TC, four nights a week for five years.
Get an aircard and laptop, 100 AH AGM battery with 120-watts of solar. Then find the best place in the parking lot (at work). A 2000 Honda is not a bad idea.