Here is a pic of the scoop (furnace ducting) under the car. Don't look at the rotted heater channel
The scoop is placed behind the torsion beam so I can still add a rear swaybar and it sits about 1 1/2" below the lower shock mount. It does not rub on speed bumps at all. I just have to install the drivers side scoop now.
I decided against the NACA ducts in the rear windows because I didn't want to cut up the windows. I want the lines of the cat to look smooth.
You can't tell from looking at the car that there is any ducting unless you look underneith the car. The whole project cost about $20 buck.
I have noticed that the fan does not come on as much now when I'm cruising. Before this mod the fan used to turn on and stay on on trips longer than 15 minutes but now it turns on and off intermittently on these trips so the duct is definately working. I'll see how it works with the second duct this weekend.
Sandeep