Most of the guys here (but not all) are into airplanes or helis. Could I suggest that you try the Traxxas Truck forum?
http://www.rcuniverse.com/forum/forumid_251/tt.htm
We'd be glad to help but not many on this forum can help.
I'm not familiar with that particular radio and don't run electric but I believe it will be a simple matter of buying the correct speed control unit.