Tachometer hook up

Hey, I recently bought a Sunpro 2 super tach [ame="http://www.amazon.com/Sunpro-CP7906-Mini-Super-Tachometer/dp/B00029JYS8"]Amazon.com: Sunpro CP7906 Mini Super Tachometer II - Black Dial: Automotive[/ame] and am trying to figure out how to hook it up. I know how to get to the coil, but where can I hook up the power, ground and lights? I have no idea how the wiring harness in these cars works so any help would be appreciated.