The instruction describe setting up the aileron servos with a Y connector for each wing , and using a Y connector to connect both wings into one channel. I am using a 9C radio, so it might be possible to run each servo on a separate channel. However, I want to run smoke as well so that option is out. I didn't want to use two channels (one for top and one for bottom) because I wouldn't be able to set any differential, so here's what I came up with:

The top wing will be on a Y-harness, so I'll mechanically set the top servos for slightly more up travel than down. For the bottom wing, I'll be running flaperon mixing (two channels) so I'll be able to fine tune the aileron differential using the lower ailerons. I will then mix the aileron channel to an aux channel and plug the top wing into the aux channel. This setup uses three channels for the wing, allows fine tuning of the aileron differential, and gives me an open channel for smoke. Perfect!