Hey John, I think PA sells a C4 bell that may accomodate the big converter. If you still plan to tow the other car with the wagon, you might check on the PA bell. I might be able to help you find a good JPT bell if needed. There are those who have adapted the Cruiso bell to a C4, and I think for your app that would be a safe thing to do also. Just don't give up on the C4 idea!