I am by far NO expert on RC stuff, and I know some guys put RC into these small planes. I had one attempt at the 400 series many years ago. I made it for 3 channels. 1: throttle 2: rudder 3: elevator. I did not set up the ailerons for movement. I flew gliders with 2 channel, to turn just give a little rudder, the model will fall, so you also input a little up elevator. I know this is NOT how real planes turn, but it works.
2 servos in fuselage of Mustang 400 series
Pushrods made from music wire
The motor is under cowling with 3 blade prop and ON/OFF swith
Just some thought for your next build... GOOD LUCK and GOOD FLYING! Mitch