Well you would only need two channels and i would guess to set it to Acro mode. The throttle channel would be the same as any other. Left stick up and down. And the stearing would be done with the right stick left and right, Aileron channel. I guessing as i never set one up.
Oh ok. When you said truck, i didn't know you meant Longhaul semi trailers. I'm sure you will be able to just assign what channels you want to do what.
Show us some pictures of the truck you have.