there is a difference between the two and here is why
GUTS -is arriving home late after a night out with the boys,being met by your wife with a broom, and having the guts to ask:"Are you still cleaning,or are you flying some where?"
BALLS -is coming home late after a night out with the boys, smelling of perfume and beer, lipstick on your collar, slapping your wife on the ass and having the balls to say: "You're next."