Hooking up a tachometer into a 03 civic

Anybody knows how to hook up a tachometer in a 03 civic coupe dx?  Any wiring diagrams for this?

It should be a blue wire on a two pin test plug on the passenger side of the battery.

No need to go under the hood for tach signal. In the fuse box, above the fuses, are several light green plugs. Look for a plug toward the left, with about 6-8 wires in it........ I believe it is the only plug there that has an orange wire in it. In that same plug, the one with the orange wire.......blue is tachometer. If you unplug the plug, it'll reset the factory radio...........don't unplug it unless you have the radio's anti-theft code.