Arrange bread slices in a single layer in an ungreased 13"x9" baking pan; set aside. In a bowl, combine cream cheese, mayonnaise and seasonings; spread over bread slices. Sprinkle with 1/2 cup cheese; set aside. Gently mix together meatballs, spaghetti sauce and water; spoon over cheese. Sprinkle with remaining cheese. Bake, uncovered, at 350 degrees for 30 minutes.