Crow, if you are still running a points type ignition you will want either a coil with a built in resistor, or, if you choose a coil without the resistor, you will need to install an external ballast resistor in the 12v supply wire to the coil. If you run the full 12v to a coil without a resistor, your points will burn pretty quickly. If you are running HEI or other electronic ignition that doesn't use points, then it's not an issue(although Pertronix still advises dropping the voltage to the coil for their conversion kits).
