Have a question for you about the Grid. Buddy of mine is currently running an older MSD 10 setup, with the coupler coil. His retards and other stuff is controlled with chips and an additional box wired in. He'd like to switch to the grid while keeping the 10 ignition. In the wiring diagram it appears it shows that ignition with a mag coil, but not sure if that's just for illustration. Will it work with the coupler coil?

There were two MSD 10 Ignitions; the original design with two coils, PN 7501, required a Pro Power CD Coil, PN 8201, and a Coupler Coil, PN 8209R. The revised model, PN 7502, required a special single coil, PN 8208. They have different coil primary voltages. Obsolescence makes it tough. If it is a working system, you can use a 7720 ( pickup green/violet to 7720) and use the white wire from 7720 into points term at msd10. I have never seen a mag coil on a 10. The diagram may be misleading with the pick-up wiring labels. MSD10 diagram