Sledgehammer, Mine is totally different. Mine is the MSD 6425 6AL, NO spark retard. It has 2 looped wire to cut if using a 4 or 6 cyl engine. Page 2 has instructions for tach. Quote:" the MSD Ignition features a gray tach output wire that provides a trigger signal for tachometers."
I had FireCore make the plug wires this year at the Nats. I told them I was using an MSD system. I hope the wires are the correct ones and not solid core. Take care, Jeff