Replacing the grill on the Impala would be a quick way to change the look of the front end.  I was thinking of fabricating something but the first task would be to remove the existing one.  I started removing the grill, but I had to stop becuse it looks like one of the fasteners will be damaged and I don't have a replacement on hand.  So this page will have to be a work-in-progress

First step is to remove the three push in fastners.  These are the same type we have encountered before.
Here is where I stopped.  It looks like the other fasteners that hold in the grill are one-way clips, similar to speed nuts but without the flats used to remove it.  I removed the driver's side headlight assembly to take this photo.  See the How-To article on changing the headlight bulbs for instructions on how to do that.  "A" is the clip I am talking about and there is another one on the passenger side.  It looks like once you remove these clips and pull the grill forward to clear the posts that the clips were on, you can lift the grill up so the tabs (B) will come out of the bumper cover.

I need to do additional work to complete this article.  Someone wanted to see the photos I had taken up to this point so I am posting this page even though it is incomplete.  I'll get back to it eventually.

No, haven't gotten back to this yet, but Mike from Cleveland said his dealership received a 2004 Impala SS Indianapolis Edition.  It has a new grille that is all black with a honeycomb pattern and a gold bowtie that replaces the OEM blue.  The grille's part number is 10341973 and should be available by special order from any local GM Parts Department. List price is $130.92.  He said he would send me a photo when he receives his unit.  Until then, Dennis sent me a link to some photos and I found one of the grille.