Don't mean to intrude, but I have been looking at a variety of options for heating my Jeep LJ and whatever camping option I wind up with. I have settled on an Espar B5, which is a gasoline fired HYDRONIC heater, not a forced air heater. This unit will be set up to heat the engine coolant, as well as a circuit supplying hot water to a heat exchanger at the back of the Jeep and/or a remote HX up in a RTT. It will also be used to heat drinking water for washing/showers. The unit will be mounted under the battery tray with the pump(s) remote mounted. I will have S&R manifolds and simple remote actuated heater valves (mechanical) to route hot water where I want/need it. The unit will cost ~$1700, plus my installation time/skills and some locally sourced hardware.
I mention the B5 because it is the only gasoline fired hydronic heater available now, as Webasto has apparently discontinued their gasoline fired hydronic model. Hydronic heating system design and fabrication is a bit more involved than hot air, but affords the same or better flexibility in distribution of the heat generated.
Cellularsteve - As to safety of gasoline versus diesel, yes, diesel fuel has a higher flash point temp than gasoline as well as much higher vapor pressure. However, diesel fuel will still burn, so depending on the risk you are concerned about, I do not think the differences between the fuels should drive your decision over which to use (including propane options). I have a gasoline powered vehicle, and I would prefer to not carry propane cannisters if I can achieve my needs with the fuel type I have on board. I can also cook with gasoline as well as light my campsite, so that is what I have chosen to standardize on.
Hope this helps.