Here's a simple how to on the removal and replacement or addition of the cabin filter on a 4th gen taurus, but it's pretty close to the same on a 3rd gen.
[img]http://home.comcast.net/~volvo9/cabfilter/step1.jpg' alt='' width='800' height='600' class='attach' />
Step 1, remove the 4 highlited retaining clips and remove the upper cowl piece. Try to pry up on the clips instead of just pulling them straight out, as they bite into the plastic and if you pull them straight out it rips up the plastic.
[img]http://home.comcast.net/~volvo9/cabfilter/step2.jpg' alt='' width='800' height='600' class='attach' />
Remove the 3 circled bolts for the lower cowl piece, and pull it straight out towards you. This is not necessary but it makes taking out the upper plastic shield and the filter easier.
Next remove the 2 bolts for the upper plastic shield over the filter, once they're removed pull the shield to the right and the pull it out towards you. You've got to pull it to the right first or else the lip on the left of the shield won't clear the shock tower. It's not too visible in the picture though.
[img]http://home.comcast.net/~volvo9/cabfilter/step3.jpg' alt='' width='800' height='600' class='attach' />
Highlighted, is where the cabin filter will be, I already removed mine before I got my camera, so if your car has no filter in it, then this is exactly what you'll bee looking at in this step. Before you remove the filter, get out your vacuum and clean out all the leaves, tree seeds, pine needles and dirt from around the filter so it won't fall in when you remove it. The filter is only pressed in place, there are no clips or anything so simply pull out the old one.
[img]http://home.comcast.net/~volvo9/cabfilter/step4.jpg' alt='' width='800' height='600' class='attach' />
Close up the the mount and the screen. If your AC
stinks like ass when you first turn it on, take this step to turn the car and the ac
on and then spray a bunch of Lysol into the air intake. Immediately turn the mode selector to the off position when your done and shut off the car, this will keep the lysol soaked ac
evaporator wet with lysol and it'll do a better job of killing bacteria.
[img]http://home.comcast.net/~volvo9/cabfilter/step5.jpg' alt='' width='800' height='600' class='attach' />
Finished!, new filter is in, I don't have pics of the old one, but it was NASTY, all the pleats where stuffed with dirt, tree seeds and all sorts of crap. I highlited some holes, there are corresponding clips on the upper cowl piece, make sure they're alighed with the holes before you try to push it back on, or you could break them off.
Now you've got a clean cabin filter, or it's the first one your car has had, enjoy breathing better inside your car.