Haha! You've got the wrong car then man if you're not feeling the dated look. I think the CTS gauges that year were CAN-BUS weren't they? You've got to have a body control module talking to the cluster for it to work.
Plus, even if you could squeeze them in there, you'll never get a finished product that is good looking. Ask Series8217 about how he feels about some of the retrofits he's seen out in Cali.
Now gauge overlays, or even new pods to use in your existing cluster, that's a good idea I think. Changing the needle color helps a lot too.
Here's a thread I did way back whenever where I changed the needle color (Cliffs blocked us from linking, just click the url once it takes you to the unavailable page and press enter):
http://www.fiero.com/cgi-bin/fiero/showT ... =printable
Speedhut overlays and new pods look great in my opinion:
This way you're working with the same technology, instead of trying to interface equipment that's completely different.