I just had this problem about a month ago. You need to use Auto Meter model 9117 tachometer adpater. The tach adapter will probably run from $30 to $50, depending on where you get it from. Locate green wire with a blue stripe at ignition coil pack. Cut in half and wire the adapter between two cut halves, inline. The adapter has its own tachometer output. **If your tachometer is capable of single pulse operation (most autometer shift light tachometers, not autogage), then you may use the black with green at your coil pack and do not have to use a tach adapter. Becaredul though because if you hook it up wrong then the car will miss fire, and thats not good..... The Tach adapter will come with instructions to hook everything up man! Let me know if it works for you!
____________________ "Drive it like you Stole it!"