Go with the Saito 100, it would be slightly overpowered but you always can throttle back. I also had a Thunder Tiger 4stroke .91 on mine but it didnt like being inverted because it put the tank too high above the carb which caused fuel feed problems. Mine runs great with the .61 2stroke mounted on its side with a pitts muffler. I think a Hog would look pretty cool kit basked with a radial cowl and dummy radial engine with a smooth running Saito.

Johnny