I basically followed the instructions and used a drill that just fitted the elevator bearing, I used the drill to mark each elevator in turn and then final drilled the horns using a 1/4 inch drill. I also removed some material from the bottom of the horizontal rear spar channel to allow the elevator horns to move the required distance to achieve full down elevator throw.
Right elevator horn drilled
Left elevator horn drilled
Trimmed the bottom of the horizontal stab to all full deflction of the elevators
