Exactly. I machined my heads to get the chambers down to minimum but I checked the deck with a precision straight edge and deemed it ok. The Surface was smoother than some of the above photos. Production machining back in the day could be quite crude. A worn out braised carbide tool with a burr on the end could really screw with the finish and accuracy. Those machining marks are a long ways from right and 60 years of engine use can mess with the surface flatness too.