RE: Kaos 40 - old timers used what engine
You will have to modify it for the normal exhaust. Sounds like the owner wanted to be different. You could get an older 2 piece crankcase engine and put it together backwards just to do it or he had a very old engine. Some Fox .60s could rotate the whole cylinder around to a different location. I would go with something .46 in a TT or OS or Magnum brand.