1988 gt Tach install Help.

[88stang_dreams]

The car i bought had a after market tach but the wiring is all wrong i belive. So i wanted to rewire it. Where did yall tap yalls 12vlt igntion switch source from? i have now wiring schmeatics so im lost on the wiring up a tach. I took off the steering wheel covers and i only see one wire coming from the igntion. So i just need to know what yall used for the 12vlt igniton source

 

[88stang_dreams]

where would be a good chasis ground? the dash board brace the metal tubing behind the dashboard? or where do yall have yalls chasis ground at?

 

[98BLKGT]

Use a digital mulitmeter and test the fuse box for switched power. Then you can use one of those add-a-circuit wires from autozone.

 

[Roland69]

what I did

red- to12 volt in fuse pannel
white- dimmer switch fuse
green- to tack wire on the coil harness
black- to some random brace I found under the dash.