Powr-Lok swap questions in 741 case.

If the rear end was quiet before, then I'd just do the minimum. Clean out the banjo, replace the inner axle seals, leave the outer seals alone if the backing plates are semi dry, clean and repack the axle bearings.

Make a holding fixture for the carrier assy. A 1/4'' thick piece of steel, long enough to clamp to a bench, drill 2 holes for the top 2 carrier bolt holes. Mount it yoke side down. Mark the end caps with a prick punch [they have to stay in their original positions]. Back off the adjuster. Bearing races must be kept together with their bearings. Remove the differential assy. Remove the yoke. take out the pinion assy. Clean the pinion assy. Check the bearing races for pitting or unusual wear. If good, assemble pinion using kerosene or light spray oil. Replace pinion yoke seal first. Torque yoke nut. The pinion should rotate smoothly. If so, remove the pinion assy., oil the bearings with diff. lube, and hide it under a clean rag.

Clean the carrier and diff. assy. oil the diff. bearings with kerosene. Install the diff. bearings and snug up the caps. Preload the bearings a little. Spin the diff. If nice and smooth, remove diff. Oil all bearings with diff. lube but leave ring and pinion gear teeth dry for pattern check.

I'm not familiar with the power-lock.