If you have the removable back plate version, then all is not so easy, pull the half shafts, remove the cover then the two bearing caps, now you have a lump in your hands that is just the crown wheel assembly, and you have already lost the settings between the crown wheel and pinion which is still in the axle, if you use a dial gauge and measure the backlash before removal then if you keep the same crown wheel you can (may be) adjust the bearings on reassembly to get the same backlash, but what about bearing pre load? chances are that once disturbed it while whine like mad after put back together unless it is set up correctly, oil is not your problem the diff clutches have gone, arm and a leg for new bits, Rick