Getting my fins on. . After removing the radiator rings from the cardstock, I make sure the notches fit to allow the fins to make contact with the tube. The instructions say to glue the forward ring on and then line up the others in the slots, I elect to just align them all in the slots, keeping the rear edge of the sail fins even with the rear edge of the tube. Once the fins are glued on, the rings will be aligned nicely...