Ok, The 90 spur and 52 tooth pinion will work with plenty of room as long as you use four, 2mm shims to space the motor mount plate up. Just put one 2mm shim at each one of the 4 bolt holes and then install the motor plate on top. You may want to use slightly longer screws, but I didn't and it works fine. If you are not sure what I mean about using shims to space it up, let me know and I will post a picture of my car.