how to ----> tach

i bought this ghetto little 30.00 tach and i cant figure out how to install it is there anyone with any experience in this area>? if so feel free to help me out thanks guys

I usta know...before I have you hook it up wrong try here http://www.autometer.com/tech_faq.aspx?sid=3

power, ground and signal...The negative or white lead on your coil will be the signal wire. Then just ground it and give it power when the key is in the on position.