Thanks for the work Dave, it does look like connecting the motor to the track would not be hard at all, although it might require some electrical jiggery pokery to go from the 12v track to the tractors supply (is it 3.7v?). I've been thinking that maybe reducing the voltage and wiring it externally into the original batteries terminals would mean that the tractor could still be used as a battery RC tractor when needed, although the RC unit would have to be stuck in the forward posistion. maybe getting hold of a geared 12v motor and a normal tractor/combine to fit it to, would be a simpler, cheaper solution, thinking about it, it seems retrograde to stick a RC tractor on a track.