Morris the loudmouth mechanic was removing the cylinder heads from the motor of a car when he spotted the famous heart surgeon Dr. Michael DeBakey, who was standing off to the side, waiting for the service manager to come take a look at his Mercedes.
Morris shouts across the garage, "Hey DeBakey! Is that you? "Come on over here a minute!" The famous surgeon, a bit surprised, walked over to where Morris the mechanic was working on the car.
Morris straightened up, wiped his hands on a rag and asked argumentatively, "So Mr. Fancy Doctor, look at this here work. I also open hearts, take valves out, grind 'em, put in new parts, and when I finish this baby will purr like a kitten. So how come you get the big bucks, when you and me is doing basically the same work?"
Dr. DeBakey leaned over and whispered to Morris the loudmouth mechanic...
"Now try doing it with the engine running!"