Viewing the arcade environment with two joysticks

[Diewrecked]

Hi all

In my original cab I have two joysticks, spinner and trackball, and I can move around the arcade with one of the joysticks and move my head with the trackball. That's all good.

I have a few other cabs I intend to do this with but for now they each just have two joysticks and I'm struggling to move my head with the second joystick. They generate keypresses so it should be trivial to change the keys in fe.cfg but I can't get the right values.

I've been editing these:
krotvertup|71|#keys|Rotate the camera view upwards.|
krotvertdown|68|#keys|Rotate the camera view downwards.|
kcameraup|82|#keys|Move the camera up.|
kcameradown|70|#keys|Move the camera down.|

.. but all I can do is move my head up and down varying degrees moving the joystick in the four directions. What am I missing to move my head left and right please?

Many thanks!