If it is a ring motor it can be converted. To do it right you need a carb adapter, a walbro carb, a cdi ignition system (CH makes good stuff and sells the hall effect adapter and magnet), and a 1/4X32 spark plug. Unless you machine the bottom end for needle bearings you will have to run the oil content at an absolute mininum of 16:1 (more would be safer) to keep from burning up the rod bushings.

On a side note BME sells a coverted SuperTigre 90 that has the needle bearing bottom end and walbro carb. It is setup with CDI and is gasoline ready. It's not cheap but it is a good little engine. Also, the gassers burn a little less than half the amount of fuel that the glow motors do so you can run a smaller tank to compensate for the extra weight of the ignition system.