I added a propane outlet in my syncro. A simple flair tee installed on the gas line to the stove, connected to a rubber (l.p. gas approved) line out the side of the cabinet behind the drivers seat. On the end sticking out I installed a "click fit" (line an air hose fitting, but again gas grade") connector. I then can plug in my OLYMPIAN Catalitic heater running on another rubber hose around the drivers seat. The heater sits between the front seats pointing backwards. I have a click fit on the heater as well. I also have a marine type barbque that uses the same hose and fittings.I just run the hose out the open door when the weather is good to barbie. All this is quite easy to do and does away with the hassle of throw away propane bottles.The click fit fittings shut off gas tight when the male fitting is disconneted so you don't neek a lot of shut off valves Be sure to pressure test any new fittings however. Use a soap bubble solution in a spray bottle to test every joint. Flaring the copper pipe is very easy if you know how. If you don't know what you are doing have someone do it for you, or buy some copper to practice on. The entire heater along with it's legs and the 5' gas hose store neatly in a small box under the back seat. 'ICARUS" Ps. I once saw someone who had a fitting that screwed into the filler of the propane tank called and "extendastay" fitting. It allow you to plug a 20# bbq tank into the onboard tank to give a 8 gallon capacity. Does anyone have any idea where/how to get one? Also I'm looking for a low oxygen alarm to install, since my heater burns oxygen. The only one I ahv found is medical grade and over $500 us. Any body ever heard of such a thing? Let me know. IcausIs it possible to connect a Coleman portable heater to the built-in 3-gallon propane tank?