I've always centered the head using the crushed solder method but you have to do it every time you pull the head. There's got to be a better way.
I've seen these head washers with a locating taper on one side that will center the head or at least make it repeatable. I've tried to center the combustion chamber on the bolt pattern before cutting but those holes are cast and all over the place. Are the people using those washers just fooling themselves or is there a way to set it up so they actually center the head?