dash wiring help?

[idriftnsj]

anybody know which wire 2 splice into 2 wire an aftermarket tach

[Brandon93240]

You should have a power and a ground, use a 12 volt switched source for the +,a good solid ground, and the signal wire gets its signal from the ground side of the ignition coil. I believe its the green wire at the coil plug, but don't quote me, I haven't worked on an E in a long time.

[jlwade]

Yes, I did it to mine. I think there is a green /black wire out of the coil.