If the switches are down, ch.5 will act as a Retract switch, which is really is but u'r just mixing. As for adjusting the elevator, I didn't think about the elevator trim. You will have to go to Subtrim. But since it's pretty easy to spot to just land it and trim it, it's fine for what I want.

I was gonna do the Y harness but I didn't want to spend more money on harness's.

Instead of splicing the wires, Why not just install one of the servo with the servo arm pointing DOWN and the other Pointing UP. It should the same.