Enabling Second Camera Gimbal Options

I have seen in different screen shots the ability to configure multiple camera gimbals in Mission Planner. I see there are several options for servo outputs for MNT2 (Which I believe is a second gimbal since MNT is the primary) How do you enable this to show in Mission Planner under Gimbal#2 or at least make the options available in the full parameter list for MNT2_X?