I'm trying to install a set of retracts to my P2. I tore out the original receiver and replaced it with a R6014FS. I want to give it a channel but I'm not sure where to wire it or power it. I also have a Zenmus H3-3D that I beleive will be on the Bus. With a 3 axis gimbal, is channels 7, 8, 9 tied up with the gimbal 3 axis? So then I would use channel 10 hard wired into the Futaba receiver and assign a two position switch? Correct? Can I power the retracts off the P2 battery? I realize that will lessen my flight time.