I was poking around a 360 engine (casting 4006830-360-10) tonight and noticed a weird stamping of the word "MAX" on the forward end of both heads on the engine. I have no idea what that means having never seen it before, anyone know? Any chance it was done at a machine shop after they milled the heads? I've read that there's a maximum amount that a 360 head can be machined so maybe they've both been taken down to that max? I can't find any reference to it being a factory stamp.