I don't believe the OS .46LA engine comes with a glow plug. Get a couple of #8 OS plugs. You also need a glow plug wrench. Might as well get the kind that looks like your car's star wrench for the lug nuts. This 4-way wrench will tighten your glow plug as well as the prop.
You also need something to start the engine. You can get a chicken stick, or better yet, get a 12 volt electric starter and starter battery. You'll need a charger for the 12 volt battery.