I am considering using the Dougs headers on my 67 Barracuda the has the 74 A body spool mount K member . I understand from posts I have read that they will work with this K member . My question now is are the face of the flanges at the head flat ? I don’t like to use gaskets , and I prefer to install with high temp RTV. I have had great success on the flat flanges , but not as well when they have the raised bead . Also are the flanges 5/16 or 3/8 thick ? Have you had good experience with them ? Thank You !