What I have done in the past, is use a propane heater from an RV. I found a really cool older suburban propane heater that fit under the rear facing seat in my 70 camper. I won't tell you that I put a small propane tank under the rear seat, because, at the time, I couldn't find a tank, from a Westfalia, to mount under the van. I'm sure you could find a tank to mount under the van. Suburban makes them that will fit. The one problem I had, was that the windows would fog up soon after firing up the heater. However, I also installed a booster fan under the floor near the front of the van and it would bring up what little heat the bus would make and quickly defog the windshield so I could drive. <br><br>If you camp, the propane furnace would be good to have to extend your camping season well into the fall. It was controlled just like your home heating system with a thermostat and you could even set it to maintain the heat in the van during the really cold snaps. <br><br>The only drawback is you would have to cut the side of the van for the exhaust/vent hole for the heater.
