Fuel Management gauge wiring

[hookemup29]

Im installing a fuel management gauge. Single engine application along with digital tach.
FM gauge has following wires:
Red wire: is batt +
Yellow: key on batt
Blk: ground
Blue: gauge light
Green: tach input. Do I need to hook this green wire up into the harnass? I dont see the need for it??? Or is it necessary?

Thanks-

[boats.net]

Yes the green wire from fuel management gauge connects to same green wire as tach at harness.