Hi!
I don't like to make you sorry but... why didn't you just install a fishing wire system (pull-pull) and mount the servo "where it should be" (togheter with the other servos at the wingsadle).
Regards!
Jan K
As Hurri pointed out, the recommended location for the servo if using a larger engine is the rear. As to the box, I considered gluing a shelf there, but the box was a better solution.