The I-6 HEI comes both ways, depending on the year. There's no real difference in performance, they're both 50,000 volt coils that will knock your socks off! Run a heavy wire, #10 or so, from the ignition switch to the (+) terminal on the coil or cap. It needs to be switched 12 V, just like the point type coil needs, but don't use the resistance wire that normally goes to the coil. The HEI coil needs full battery voltage, with a big enough wire to flow a strong primary current.
Jerry
