5 Inch Monster Tach

Alright... I just bought a new talon and the kid i bought it from had a monster tach in it but uninstalled. He did not give me the directions. So anyhow there are three wires coming from it, a black, a red, and a green. I know that the green hooks up to the back of the gauge cluster. The black wire is the ground wire and the red I am clueless. If anyone has hooked one of these up please let me know where it goes. The black wire (ground wire) also controls the light... So the tach lights up, but does not read. Thanks alot...

http://www.vfaq.com/mods/ecu-harness-1G.html
21 Crank angle sensor (RPM)

:useless:

Thanks Joe...