Here's a "real" Knife.

This is top of wing, looking down.

Aileron servos are outboard. Rudder and elevator are inboard, throttle is in the middle on the right side.

Spacing is determined by:

Rudder/elevator- leave enough room to clear the fuse with your servo arm

Ailerons- So the control horn on the plans lines up with your servo arm

Throttle- close to the inner as you can get without interfering with the pull-pull arm (throttle is push-pull)