No can do! That one-wire switch is probably a Ford starter button, and pushing it grounds the wire to the dash. Ford used a magnetic switch in their starter circuit for about 30 years that required the single small wire attached to it to be grounded to pull in the magnet and connect the battery to the starter. You would need a relay in the circuit to energize the starter solenoid, and ground the coil with that button to make use of it in yout harness. Check it with an ohmmeter, and I'll bet you get continuity from the single terminal to ground at the switch mount when you push the button. Jerry
