The OE shakers were closed off at the back, at least later ones were. People perforated the intake area at the rear with a drill and also put holes in the air cleaner lid outside the filter to make theirs functional. The duct piece may be visible in a pic posted earlier. You bolt scoop base to fuel rail, put silicone sleeve on TB then jam duct on and screw to big front piece then the arrow goes on. Filter is still up in the air but a cone no worky.