I called and talked to TTI today. They did not think their headers will fit the A body engine. They also said if I buy a set to try they are mine no matter how much damage if any. I understand but didn't really care for the guys tone.
He did give me the name of the guy who they began to make the poly headers for to see if he had researched the possible swap. He was not encouraging at all. He would be shocked if they fit. FYI.