I had my 289 rebuilt two years ago and following my engine builders recommendations I bought this unit and a flame thrower coil. This is a truly easy installation. Again, following my engine builders recommendation, I bypassed the ignition resistor wire so that a full 13.8 volts would hit the coil instead of the point saving 8.0 volts. I then re-gapped my plugs to .040. Here is the downside, my 7mm plug wires could not handle the extra high voltage. A new set of 8mm wires topped of this installation. The best thing is, gas consumption went from 22.3 mpg to 24.7 mpg highway.