In "he'll quack you up," "quack" is replacing "crack."
Enjoyed your review, agree with almost all your comments. In the first panel of "Tootum-Too" I already assumed that "Wak!" here was meant to connote laughter.
Love the turnstile and the secretary-stork!
That's how his studio mate, Elmer Fudd, would say "crack you up!" They should have drawn Elmer saying that with a speech balloon pointing at Daffy.
