Air Deflector

I'm talking about the three pieces that attach to the bottom of the front bumper of non-AA cars. Now, I ordered all three pieces from Norco Mitsubishi. They came but don't look like what on the car but I can't find a differing part number. Now, what's different is the lip, there is an example below. Now, I don't know if the lip is separate from these pieces but I want to now if the lip need to be there. Will this effect my cooling or aerodynamics in a negative way?

Anyhow, here's the picture. You can see the black pieces I'm talking about on the sides, the center piece is gone.

http://www.synapsepc.com/Hosting/CarDomain/Stealth/Images/Page%203/Front.jpg