Need to know a little more about your project first,
What engine is this? Magneto type Ignition or Electronic? Starter / alternator, or Alternator with system Diode (like an old Honda)
It would be good and very helpful if you could snap a few photos of it and post them here , as well as any "Extras " you can think of..
I have a Schematic maker, but I need to know what it is I dealing with before drawing anything.