The Rebels engine choices were the Sachs with 4 speed and the AH58 Tecumseh from what I've seen, I had an opportunity to buy a hacked up one without the tank and I'd pay with a briggs engine but passed because I'd never find the parts to make it whole. It is one of my bucket list bikes and even in Oklahoma they are super rare, this one you found is the second one I've ever seen in photos and I've only seen two in person. The 1st was a sachs powered Rebel flying up Peoria ave. in Tulsa circa 1971-72 where they were made and the second was the unfortunate one I had to pass up. I have not given up on finding at least an unmodified roller to build. I'd pay moon rock money for a complete survivor example with the AH58 or Sachs either one, they are goofy looking and you either love em or hate em like the MTDs. Great find Joe, I know you'll treat her right.