Just make sure you shim those spider gears when they are clean and dry, the instant torque of those breshless motors will slightly flex the composite cups and the gears will spread and you can easily strip em out on the top bevel. Even with my LRP/Picco engines I had to put 2 shims behind each spider gear for correct lash. Stock diffs normally come with one(and in some cases some have come with none)which many times is not correct or enough.