Turn the air box bottom over so you are looking at the bottom of the box. Find the spot where you will drill a 2-1/4 inch hole. (See red dot in picture.) The drill center is right at the pinnacle of multiple curves. Sorry but I found it impossible to make a template for this but I think you will find it correctly based on the pictures.
Drill the 2-1/4 inch hole in the bottom of the air box and then take your round rat-tail file and enlarge this hole until you can fit the small end of the newly fabricated inlet tube (Shop Vac tube) through it from the inside. Make this a tight friction fit. If done correctly the new inlet tube will fit all the way up to the U-shaped channel.
After fitting the hole to the newly fabricated air inlet tube, you will need to drill 3 holes through the new air horn u-shaped channel and the air box. Position the air horn at approximately a 45-degree angle to the long side edge of the air box. This angle is not critical but should be close in order to run the snorkel inlet hose to it. If your setup is different just point the new air inlet horn in the general direction of where the inlet hose will be. Drill three small holes through the air box and the new air horn u-shaped channel. Try to space these holes as evenly as possible around the air horn but consider you will need room to screw in the 3 self-taping stainless steel screws in these holes.
Put a 1/8-inch bead of RTV around the new air horn on top of the U-shaped hub (outside flange) and slip the air horn through the inside of the air box. Screw the air horn down with the 3 ss self-taping screws. (The screws go on the outside of the air box, through the air box and into the air horn u-shaped channel.) These screws provide a good mechanical connection between the air box and the new air horn. However this connection must be more air/water tight.
Apply a liberal coat of RTV to both the inside and outside of the air box where the new air horn comes in contact with the air box, Get carried away here! But be neat too! Be sure to cover the mounting screws as well.Set the air box bottom aside to dry. All modifications to this part are now complete.
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