You can pick up small rare earth magnets that will work fine from Radio Shack. I think they are 1/8". Yes it means 28 degs. BTDC. Check the polarity needed for the magnet before mounting it. It matters which pole of the magnet faces the pickup. I connected my ignition system up, put a spark plug into the lead and then passed the magnet by the sensor until I found the correct pole to face the sensor. I marked that side with a sharpie so I could tell when it came time to mount it. The next time you need an EI call and talk to Bill or Terry at CH ignitions. They sell a version of the RCEXCEL made for CH and are some of the nicest folks you will ever deal with.