Unless you have done it before, the general consensus is to take it in. It is more of an art than a simple mechanical procedure.
Personally, I recommend that you talk to River City Differentials (Sunrise Ave. near dismantler row in Racho Cordova). Best price, best service I found when doing my truck. In and out the same day, good work and $300-400 cheaper than West Coast Differentials down the road.