It looks like it would have to be an airplane engine, the OS "C" is real tough to find, and demand seems to be keeping prices high at auction as well.

Jeep, what engine was this and what clutch did you end up using? The X-Factor has lots of space around the engine, so mounting should not be a problem (I'll take some pics & post). I'm more concerned with the clutch, which has to be heavy duty for the rock-crawling scene.

Thanks.