RE: t6exhp dual aileron servos
I am not familiar with that radio. Generally, if it is a computer radio, you would use the Flapperon program to mix channels 1 and 6. If it is not a computer radio then I know Futaba makes a device like the JR Matchbox that you would connect to the Aileron channel and then connect both Aileron servos to the Matchbox. It allows you to connect up to 4 servos to one channel and Match them for Neutral, End Points, and Servo Direction. It is much more reliable than a Y harness and much more versatile.