Check the thread
[link=http://www.rcuniverse.com/forum/m_1267448/tm.htm]Gas Fuel with Glow Plug, No Ignition[/link]
in the Engines-Conversions Forum.

They started out trying to replace the sparkplug with a glowplug for gasoline use, then moved on to blending 2:1 gas-glow to run a engine with a glowplug. Seems you could read up the info on the mixes, and get a nice recipe to run your OS46 or TT42 or whatever cutting glow with plain old gasoline. $2.40 unleaded cut with $17 glow brings the $ spent fueling the plane down nicely. Get a recipe from them guys, they've done all the leg work already.