3 Racing Motor Mounts
Responding to Nova--
The motor mount/heat sink that comes with the chassis is different from the separate one; it has one hole (closest to the spur gear) in a "set" position and the motor rotates around the set side. The separately available one is a linear left-to-right style, with both screws able to move. I find this easier when using aftermarket (conventional 48 pitch) gears, as it's easier to "eyeball" the adjustments for mesh, which essentially have to be made with the motor out of the car.
The easiest way is to use Tamiya's motor mounts and stock or high-speed gear sets, since you don't have to worry about mesh---it's set and unchangeable in that configuration! Those ratios also work for most applications, but of course there are those of us who are just crazy enough to want to try everything...
TVree