This site helped me to fix this problem, so hopefully these photos help the next guy or gal.
Fan Clutch Replacement for a 2003 GMC Envoy:
-Remove the fan shroud bolts.
-Disconnect wiring harness for the fan clutch.
-Remove wiring harness from fan shroud.
-Loosen the 2 trans cooler lines from the fan shroud. Do not disconnect the lines, just move out of the way to allow the fan shroud to move.
-Disconnect the radiator hose above the fan shroud (please make sure that the engine is not hot or else you could get burned). Some say this not necessary, but it makes it easier to move the fan shroud and later to remove the fan clutch.
-I never have the right tools so I had to use a 1-7/16" wrench on the fan clutch nut (the correct size is metric). Also, not having the appropriate tools, I jury rigged a screw driver between the 2 bolt heads on the pully that the fan clutch is connected to. Turn the fan clutch nut counter-clockwise, note that on some other cars or trucks this may be reverse threaded, but on the Envoy it is not. Also note that some people have had a hard time cracking this nut, but others have not.
-Remove the fan bolts, let the fan hang.
-Remove fan clutch by wiggling it through the space between the fan shroud and the radiator (make sure you don't bang the back side of your radiator, it is like playing "Operation")
-Reverse these steps to reinstall.
-This was a really easy job, only took me 45 min. Hope this helps someone in the future.