Even if you have 2 RX one of the elevator servos needs to be reversed Ive seen people put the linkages backwards on one servo but the acuracy of the surface will be very bad due to the geometry of the linkages. Im unsure why mstroh3961 said one aliron needed to be reversed a simple Y cable would work. As far as adding the 2nd battery I allways put a Y cable on the rudder servo And plug the switch into that then go to the 2nd battery from the switch You can plug a battery into any channel on a RX and the system will power up. I use the rudder due to the fact mt rudder is my biggest servo and I fly in a hover or a knife edge on all my down wind legs and do a touch and go on my return. They call me touch and go Dan at the field my wheels allways need lube. maybe this year Ill do that the squeeking is getting to some of them . But the rudder usses a lot of juice however you will never get the batteries to drain even and the whole Idea is redundancy for safty and to protect your investment. Good luck