[sorner]

It's doable, as long as you have the right style oil pan, and right style flywheel for the drive shaft hub. If it's an engine from a Cub you should be fine there. You need to do a relay for the ignition since you're going from points ignition to magneto, so instead of applying power to the coil to run the engine, you need to ground the magneto to stop the engine. Do NOT apply power to the magneto or you'll fry it. You're also going from starter generator/giant voltage regulator to alternator under the flywheel and regulator on the side of the engine shroud. You'll just need to account for some wiring changes and everything else should transfer over. Oh, and the PTO will be a electronic clutch instead of manual.

Unless you want to get real exotic and put a manual clutch and starter generator on the mag...