Heat oven to 350 degrees F (or 325 degrees F for dark or nonstick pan). Make and cool cake as directed on box for 13x9-inch pan.
Cut cake as shown in diagram. If desired, freeze cake pieces uncovered about 1 hour for easier frosting.
On tray, place cake piece 1. Frost with about 1 1/4 cups frosting. Arrange pieces 2, 3 and 4 as shown in diagram, trimming to fit, standing up piece 3 for top fin. Trim point of piece 2 for nose of shuttle. Frost cake with remaining frosting.
Use licorice to make diagonal lines across nose of shuttle and to outline top fin. Use baking bits to outline tip, wings and back of shuttle. Add large and small stars to wings and back; add round candies to both sides of fin. Write 'USA' or another message on top of fin with decorating gel. Insert candles at end of shuttle. If desired, just before serving, light candles for 'liftoff.'