I assume you are talking about the ports on the intake. The 216 ports are smaller. You have two choices to fix that.
1.) You can have a machine shop enlarge the ports so they match the head ports and accept the 235-261 alignment rings. 2.) You can call Steve at Buffalo Enterprises - phone number: (360).652.7684 and I believe he sells alignment ring adapter-reducers.

By the way, I like your Stovebolt name!! grin I hope no one gets us confused!

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