It's not a hard job.....
The only special tool really is the pinion depth gauge. Once the pinion is installed properly with the crush ring and properly tourqued bearing drag, the ring gear is set for backlash, check your tooth pattern just to make sure the pinion and ring gear adjustments are on, and voila'. You can do it without the depth gauge, but you may need another crush ring if you aren't lucky.
Much rather do than a clutch.
-J