Sam,

I used the OS 1.08 with the Slimline pitts style and I had to move the engine forward about 3/8 in. The engine fits completely under the cowl and with the Bisson style muffler mounted to the side I think it might fit without doing a lot of mods. the cowl or moving the engine on the mount. My only concern was enough airflow out of the cowl to let the heat out. Good luck

Larry