Actually, it's not all that bad if you don't mind spending a bit of time & cash.
Probably the easiest way is to find the cluster you prefer from eBay or another source such as LKQ,
http://www.lkqcorp.com/home/home.asp.
As best I can recall, I got mine for about $90 from LKQ. Doesn't matter what year model - all transfers are plug & play. The change
must be certified to ensure compliance with federal mandates & keep your warranty in effect!
Once you have it in your hot little hands, the simple solution is to have your dealer handle the swap out - they can contact SPECMO
http://www. specmo.com who handle GM work of this type, & send it to them. SPECMO will program your new cluster with the mileage settings of the original & send it back to your dealer who will then install the the certified replacement. I think my total cost, including purchase of the unit, certification & installation was around $250. I had the transfer done while the car was at the dealer for warranty work, so they had the car for 3 or 4 days - provided a free loaner since car was in for other work covered by warranty.
Some folks have dealt directly with SPECMO & saved themselves a few bucks, but doing it this way one must send both units to SPECMO. I'm not real sure if the car is useable without the cluster.
I'd go for it!
2004 cluster swap?? 
Sorry,...couldn't help myself here...
