Off topic, but I also remember a spark plug shaving device that some race engine builders used to trim the gasket surface of the plug shell down, along with a torque wrench, to clock the ground electrodes at exactly the same position for every cylinder. Now, that's really getting ridiculous about "blueprinting"!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!