[johnta1]

Here's what the MSD says:

Power Cables: The heavy Red connects to the battery positive (+) terminal. The heavy Black connects
to the battery negative (-) terminal or other good engine ground.

Red: Connects to a switched 12 volts source.

Orange: Connects to the positive (+) terminal of the coil. This is the only wire that makes
electrical contact with the coil positive terminal.

Black: Connects to the negative (-) terminal of the coil. This is the only wire that makes
electrical contact with the coil negative terminal.

White: This is one of the wires that provides a trigger signal for the MSD. It connects to
the breaker points, electronic ignition amplifier output or to the Yellow wire of
an MSD timing accessory. When this wire is used, the Magnetic connector is not
(Violet and Green wires).

Violet and Green: These wires are routed together in one harness to form the magnetic pickup connector.

They plug directly into an MSD Distributor or Crank Trigger. The Violet wire
is positive (+) and the Green wire is negative (-). When they are used, the White
wire is not.

NOTE: MSD SCI Ignitions share the
same wiring as the 6-Series.