That's probably it. I'd have to see if I still have the reciept.
Google turns up a finish option AK5000, called Aluminum Koat and Aluma-Kote.
I remember it being rough and bit more white than shiny but can't be sure. It was my initiation into installing headers. :LOL: A few weeks later my buddy's brother tries putting a set in a full size Chevy Blazer. There's tons of room in that bay and they don't fit either! However he was willing to take another shot and the set he exchanged 'em for fit reasonably well.
Anyway, according to the label here in this photo AK5000 was hot sprayed on (probably flame or plasma) but no claim to having ceramic in the material.
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