[suicideneil]

It wont fit, and you cant buy the adaptors anymore- you would need to mess up your X-braces.

The thing is though, GorillaMaxx designed the G2/3R chassis as the first electric conversion for the Revo, so it uses the only electric model based tranny that was available at the time, the 3906 one (as the x-braces are the same between the G3 and G3R).

Traxxas then bought out the Erevo a few years later, so the G2/3R is basically redundant in effect.

If you want to make a G3R, you have to use an old emaxx tranny basically, and the one I linked to on fleebay would be your easiest option infact.