sorry, it wouldnt let me send you a reply with the message thing:

hey bro, i dont actualy have a "how-to" for the grill, i just have pics of it in. all i did was: on the center grill theres no problem getting it in there and screwing it in. its just a couple of screws and clips thru the plastic, 4 i think. the side vents are a bit more difficult just because of space confinement. i placed the grills in, marked (scratched)with a small nail where the screws go, took my swiss army knife leather punch and started a small hole and then used a short screwdriver to screw the screws in.
ya just have to be a little inventive to get the holes started, after that, its all cake!
hope this helps, lemme know if you need anything else.
tim