I know these might not be the most purposeful DIY ducts, but they actually do something and they look pretty good.
I used 2.25" flex aluminum duct. About 18" for each duct.
I cut the plastic fog light blanks with a dremel, but be careful, the plastic likes to melt while it's being cut. This leaves a lot of burrs that need to get easily filed off.
Next, cut about 6 inch slice down the side of one end of the duct.
This is going to be the air intake side and will be stretched out over the cut plastic insert.
Cut the whole side off at an angle making sure if fits properly over the insert.
To attach the duct to the insert I used silicone and some hot glue on the outside to hold it for the time while the silicone dried under the clamps.
Clamp the crap out of it to make it a tight fit.
Next I used a 2.25" hole saw to cut through the wheel well from the inside. I didn't take any pictures of this step. The duct is easily bent to exit where it is needed. Then I simply pulled the tip through the wheel well hole. It's really snug so it won't go anywhere.
I plan to remove a section of the interior dust guard around the rotor to allow better air flow.