we just finished putting one on the 2003 sierra we are doin....fairly easy...as has been said you need the brake pedal to go with it and you can order the power steering lines from GM....only "fab" you have to do is drill a hole in the firewall for an bolt thats doesnt line up from the hydroboost....other than that it is entirely bolt on....my buddy did it in about 2 hours and he is not very mechanically inclined
her is a link to the how to on gmful
lsizehttp://www.gmfullsize.com/forum/showthread.php?t=156800