Fitting TTi headers on a 273

I’ve got milling machines - so we will be able to mill them flat if necessary.
Good idea about the support from middle to end. Removing it will help pull the header down.
That sounds good. The trick will be fixturing it. Others do it. They may use a jig on a belt sander. Headers by Ed used to do it. Calvin Elston and all of the custom builders do too. This evening I can search on Speedtalk forum - I know it came up in discussions.

I kindof hesitated to post these here, but this what I found.
I did the best I could using a glass plate and sand cloth, but the overall arch was more than I could address. I wasn't terribly concerned using the fat gaskets and such a thick flange.
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