How do you remove front passanger fender in a 2004 Chevrolet impala?

If it is the same as the '03 then you need to remove the headlights first. There is two white plastic tabs that hold each headlight in, lift them straight up and the headlight will come out(one may be hiding underneath the little plastic cover right behind the fan shroud i cant remember, you'll find it though) then release the wire harnesses from the headlight assembly. Next (get a buddy) remove the bolts(2 on each side, 13mm i believe) that hold on the hood, then remove the shocks and set aside the hood. Remove all the fasteners that are in the wheel well, then on the skirt at the bottom of the fender remove the plastic clip, this will allow you access to the (2X 10mm i believe) bolts that hold the bottom of the fender on. Going in through where the headlight sits you can reach underneath (or get down and look) and find the two bolts that hold the fender down to the bumper cover, remove them (11mm BTW), this will allow you to pull on the bumper and get access to the one bolt (10mm) holding the fender to the body. Remove the wheel well and pull out the plastic/foam insert between the fender and the door hinges and remove the 10mm bolt there. Remove the other bolts that hold the hood/hinge assembly and remove it, you should now be able to remove your fender. This is probably too late, but good luck