Mutlifunction Tachometer Gauge ?

I have a set of 02' Yamaha F225's on my boat with the multifunction tachometers gauges. The autopilot I'm installing on my boat requires a interface with the tachometer and I'm not sure if there is a easy way of tapping into it or not. I don't have a schematic for the gauge, so I've looked at all the posts I could find here to see if someone might have asked this same question. I've also noticed in the maze of wires there happens to be one bundle that has some female ended plugs covered in a clear soft plastic. I figured I might be able to tap into these since they are probably used for diagonostic purposes if the motor is getting worked on but I wasn't 100% positive. Any help on tapping into the tach wire which I think also goes to the ignition would be greatly appreciated.
Thanks,
JPT

[boats.net]

The green wire is the tach signal lead and should be an open green wire terminal where tach connects to harness from key switch.