I'm having the same sort of issue with a machinist who really doesn't want to grind a crankshaft my way. That's one of the big reasons I went ahead and bought a grinder for my own shop. I did find an old geezer (2 years older than me) who agreed to grind a prototype shaft to my specifications for half what the other guy wanted. That will allow me to get a dyno test engine assembled while the equipment and power wiring is getting rearranged in my shop for several pieces of equipment that require 3 phase power. Once that's done, I will be able to modify crankshafts, cylinder heads, and blocks without relying on anyone else to "do it my way"! Frank Sinatra was not the only guy who ever believed in that principle!
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!