For everybody that has a front lip or splitter attached on the bumper.
I may have a solution.
Checkout the air inlet on the Ferrari.
You can mount this in the bottom of the floor to get the airflow to the brakes.
I have seen these inlets in racing shops too. i can't find a picture of them online and I don't know how they are named. Just cut a triangle out of the bottom of the floor and again rivet it in... On the ones i have seen there is always a connection for ducting on the 'back'.
Racers have them installed in plastic windows Or installed them in the rear body to get some cooling to the diff or rear brakes.
Bad picture...but the E46 M3 is overtaking the Saleen! They are about the brake for the first left hander on the Zolder race track in Belgium..
Maybe someone can find the ducts somewhere online