Several days ahead or day before serving, mix in a large bowl with mixer at medium speed the chedder cheese, cream cheese, sherry, ripe olives, Worcestershire sauce, onion salt, garlic salt and celery salt. Now shape mixture into a ball, wrap in foil, then refirgerate until needed. About 30 minutes before serving, remove foil from cheese ball. Reshape into ball with hands, then roll it in the dried beef until it is thoroughly coated. Makes about a 8 cm ball.