what 1 wild RT said, Nothing will be exactly what the listed dimention is. Mill the head deck to get quench then set the heads/head gaskets on the decks and mockup the intake w valley pan and check the head/intake intake port(s) alignment w valley pan then either mill the head intake face or the intake for a perfect fit/port alignment. For either of these 2 checks fyi the head gasket only compresses a couple of thou so mock it up & see where you're at.