Joystick, DO_SET_SERVO for extra buttons

Hi everyone,
I am trying to use the buttons on my joystick to operate three receiver controlled switches on my rover/boat. I can use the extra channels to operate the lights etc via the X & Y axis on the Joystick but that leaves me one channel short. I have 7 extra buttons on my joystick so I was hoping to map the channels to the buttons but can figure out how to do it.
I’m using APM 2.6, MP, Turnigy receiver servo switches, 3DR radio, Thrustmaster T-Flight joystick.

I received advice to set the buttons to DO_SET_SERVO so I have done that.I have followed the given instructions and set up the DO_SET_SERVO on two channels one with a low PWM 1000 I think and the other high 1900PWM.
But where I am stuck now is the DO_NOT_SET settings options asks me for the “Servo #” as I have the switch plugged into ch6 I assumed that that would be the servo number but no, I have also tried “A6” neither work.
Can you please tell me what the “Servo #” correlates to on the APM outputs?
Would add a image but there doesn’t seem to be an option on this new site :frowning:
Thanks in advance

Ok with more reading I see that the Servo# correlates to the servo output pins. So I think I have it set correctly, which leaves me even more puzzled why it is not working.
Can anyone tell me what I might have missed? Do I have to change any other settings? Because I am only making these adjustments in the Joystick configuration panel.
Thanks in advance,

MP does offer the options to use a hat switch as an axis, and also buttons as an incremental axis. You would select Hatud1, or Hatlr1. This creates 2 new axis, and you will need to hold and release the hat switch to control it. Along the same lines Custom1 and Custom2, set the axis to either of these, then the buttons to button axis, when pressed it goes to one extreme, and the when released it goes back to the other extent.