Newby Project. Skywalker, 3 channel fixed wing without rudder

I see that a similar topic was raised 4 years ago, I would imagine that this thread is dead.

I am a newcomer to the world of RC I have built and flown a tri copter and I will admit to my share of fly aways, I have added Ardupilot to this and I am very pleased with it.

I am starting a new project now, I was offered by Bang good on their latest anniversary a Mini Skywalker which I bought.

I have started glueing it together and I have found room for an old Ardupilot APM 2.6 in it, when I looked in the docs I didn’t see any for a 3 channel fixed wing without rudder, I am also following the series by Iforce2d and painless360 but both of them are useing “Bonsai” type planes.

So to make it short which channel numbers should I use for

the left wing servo
the right wing servo
the rear wing servo
the propellor esc

I am so new at this please help, any other info would help me would be apprciated

regards FP