I have a 1991 M3 and I just purchased the Evo box and the Tow Hook covers. I have yet to install them. My question is this: Will I still use the ducts that are closed with the tow hook covers? If they wont be used then how does the box receive air? Should the airbox be "pluged" into the duct next to the radiator althought the ducts are blocked by the tow hook covers?