The firewall was a bolt up but the rear mount needed rework because the motor is shorter than a Hacker. I had to find someone that was going to Japan to get mine because no one has it in the US. Futaba told me they wouldnt ship to the US and none of Japans hobbyshops that carry it will sell outside Japan. Its a great motor and if you can get one you will be happy with it. I wish they would just go ahead and put their OS badge on it and start selling them in the states. 18x10 xoar at 7400rpm gives 14.5lbs static and 63 amps on 8s 20cand runs cool