Online Community of Zenith Builders and Flyers
There is a fellow on this site named Wayne Tyson who owns a CH750 with an IO-240 on it. Try checking with him.
I installed an IO-240 B on my 750. It uses the same engine mount as the O-200. If it has the propeller extension/ adapter the regular O-200 cowling should work, not sure about that, depending on which exhaust you use. I didn't use the extension/ adapter. So modifications had to be made to the cowling to clear the plenum. Send me an email if you like and I will enclose some pics.