Appropriate mode selection for elevator over-write

I’m trying to dynamically set the maximum allowed deflection of the elevators by changing the vehicle parameter RC2_MIN (using an Odroid to connect to a pixhawk through the telemetry port).

I want to command an elevator deflection of, say, -20 degrees, but due to the Odroid setting the minimum deflection at -10 degrees, have the actual command sent out to the elevator be -10 degrees.

In manual mode, changing RC2_MIN doesn’t do anything since commands are directly sent over to the elevator. Stabilize mode allows me to do this on the ground, but in the air, the autopilot takes over, which I don’t want.

Is there a mode which can accomplish what I want? Or maybe a parameter I need to change?
Basically, I want a manual mode that takes RC2_MIN into consideration.

Thanks for any feedback.