Next you'll need to access behind the fender splash guard- a few little plastic fasteners. I did this up on my ramps to to ease access. Once you have access you'll see the fog lamp holder just slides out (held in w/ three tabs). You'll have to affix your duct to this plate- takes some cutting/sanding to get it just right- I don't have pics of this as I did this last year. I used an epoxy and bent of the sheet metal in a few spots to keep the ducy attached.
Here's a few pics of the plate w/ the duct attached: side view (you can see the reducer as well) :