I ripped all of that out the tubes are fine just sitting behind the grille. I could not figure out what they were for either, but I assume they are better out then in you are getting more air to the engine. I have a question thought this might be a good thread to run it by. I will try to be detailed so you can understand what I am saying. I thought about doing the same thing you did only when i heat up the end of the tube to widen it, put a piece of 3-4 inch PVC ring inside. Reason being that way i can clamp off of it. It will be really ridged and stiff. After you have melted it and put the larger ring in there buy a piece of three inch aluminum pipe run it off the end behind the grill and attach a filter. In other words on your last picture run a 90 degree three inch piece of aluminum and put a filter on the end and connect it to the end of the tube. Remove both box filters and repeat for both sides. It will almost be like a dual needswings intake only using our stock air boxes. If anyone can get the visual let me know lol and tell me what they think I might try it.