Basic Tilt rotor VTOL setup

[First time PX4 user] I’m trying to setup a 4 motor tilt rotor vtol. It is not clear from the available PX4 getting started guides and airframe referince which airframe type I should use. I have tried “Generic QuadPlane VTOL” as well as “Fun Cub Quad VTOL” but none of them seem to specify a channel for the tilt servos. Is there some critical bit of documentation out there somewhere that I have managed not to find, that would show me the way or will I need to start understanding and then messing with .mix files?