Please help! Bobcat A300 and BSG

[CTS1999]

I picked up an A300 yesterday. I need to get 12 Volts to the grapple attachment. I would love to use an existing button on the joystick to send the power out there. The horn button was my first thought. Apparently, this unit was built without a horn. I found what I believe is the plug for the horn in the wiring harness but I'm not getting power to that plug when I push the horn button. I looked at the harness going into the left joystick. There are only 4 wires going into the sealed circuit board. There are many more buttons than that. Am I missing something or does that mean several of those buttons are not wired up? Any help from anyone that has wired one up is much appreciated?