My forced cold air induction cost me $2.
If you don't have a 3-1/2" hole saw it will cost you about $40
All you do is saw a hole in the firewall location shown after folding back the insulation.
Saw another hole in the lower rear passenger side of the stock airbox.
Connect the two holes together with 3" RV dump or clothes dryer hose.
No clamps or sealing needed, the offset inbetween the holes will lock the hose in. Leave the stock air hole open.
What you are doing is cutting into the same channel that force feeds air to your vent system.
On my test hill this mod lowered EGTs by 150°.
This is a copy of the same principal of the best air intake ever made, the Scotty.
It's no longer available, Scotty wanted to do something else.
I did this mod over 10 years ago, no problems at all. No water gets in the filter box
for the same reason it doesn't get in your vents.
Beware, this mod is loud, sounds like the turbo is in your glovebox.
Mod installed and box pulled away for clarity below