A friend of mine with an 02-03 WRX put in the gauge cluster from an 04 STi it immediately blew the fuse for the stereo.

He also has the wiring harness from the 04 STi cluster, but can't get the stereo to work. anybody have a write up for this installation?

http://forums.nasioc.com/forums/showthread.php?t=322230&highlight=sti+cluster
It's all there, happy reading ;)