Please help with this challenge:

I am almost ready to maiden my twin F18 and cannot figure out this programing challenge: I have tail rudders on rudder port on receiver, and I have nose wheel on Aux 4 and slaved to rudder channel on program mix 51. When the gear is retracted and the nose gear retracts, the pull pull direct cable linkage remains tight. The nose gear retreats nicely, but if the rudder command is given while the nose gear is in its up position, the nose steering servo now puts extreme pressure on the cables.

I would like to disable Aux 4 (steering servo) when the gear toggle is put into the retracted gear position. Is this posible and if it is please explain how to do it step by step.

Thanks

Kevin Marks