I put a saito 82a on mine and had to cut a hole in the bottom and mount the elevator servos just behind the wing hold down block. Used pull- pull on elevator and rudder. Then put the battery on the fire wall behind the motor to get it to ballance at 5". My canopie also had a bad dent in it when it arrived. I called Chief and they are sending me one. I'll fly when it arrives. This plane will never ballance with the servos in the factory planed space without using lead when using the 82a. Weighed it using digital bathroom scales and it came in at 6 lbs+. the scales don't do ozs. Anyone using the 82a let me know your set-up for ballanceing.