Originally Posted by Blue68Camaro
So will rectangular headers work on a head with "D" ports?
Yes and so will full round tubes as long as they are outside the head openings. Put a gasket on the heads and see that it clears the d-port on the heads, then put the same gasket on the headers and make sure they are outside the head ports. No one makes a header that is a perfact mact to the ports on the heads, the main concern is that the head empties into the header without hitting the flange of the header or the tubes in the flange. i run 1 7/8" hookers on my brodix-1's and i can assure you the exhaust ports are not that big.
Zip.