well i got back a e-mail from the muffler guy and he said to mount the motor and then measre what is left behing the motor so i just order my motor build the body but not gule the firewall in so i can get the hole right and we will see when i mount it no big rush as for the wings maybe atfer mounting every thing she will balance out but if you dont want to do that i would use the lead weights and put it in the begining of the wing close to center and the center section so its about center of the plane thanks rye now i know what i forgot when to home dept to get