I just ordered the Sure Fly ignition for my 1966 C. I talked to the SureFly people at Oshkosh and told them I had replaced my old vibrator with a SlickStart unit a long time ago and asked which mag I should replace. He said I could keep the SlickStart and left mag, installing the SureFly on the right side, then I would be using both to start the engine, which is what I am going to do. I had replaced the old vibrator because my points were shot, it made more sense at the time to go with the SlickStart.
I went with Aircraft Ignition Services for the harness. The harness was $259.00 with 90 degree plug fittings plus shipping. Both SureFly and Aircraft Ignition Service have been very nice to work with, we’ll see how delivery goes.
I have a friend with an O-540 on his Comanche who can’t say enough good about his results, which encouraged me to install one. I’ll report back with any interesting observations on the install.