Well you'll need a box of band aides , socket set, mechanical abilty, a bottle of hard liquor to get enough balls to tear apart your non malfunctioning diff, time, time, dial indicator, white lithium grease, etc....
I know how to do gears and have done them before. This is a job that you want a proffesional to do. Anybody who has ever had a diff lock up on them before knows why. Skimping out on $ now will cost you three times later. They also suck if you don't have a lift. Just spend the $180-$250 to have them installed.