Rear wheel build.
It's all apart no better time to get the hub cleaned up. I think use a bit of restraint wnen cleaning spoke marks, when you rebuild the new spokes will be in the same place as the old, don't try to
completely remove those dents. You will end up making the flanges thinner than is good for them or you. Also the dents make setting up the new spoke pattern easy peasy.
Insert all the innners first. They go in the holes between the holes with dents and will lay in the opposite direction from the dents. Inners have less bend at the head. mikes has them separated in the package, if not sort your set into inners and outers. Once all the inners are in, cross them, watch your over under, all "top spokes " above all bottom spokes.
set the rim over the hub a couple 2x laid flat will set the offset fine for this part of the process. Rear wheels are easy, the angle of the holes in the rim makes getting the pattern going simple. Watch the spoke over under and crossing or you will be undoing spokes to free up a tangle in a bit.
Start threading on nipples, just a couple of turns, do NOT thread them on very far. Keeping the rim loose aids getting the last spokes in the holes without a fight. Shake the rim a bit to get room to insert the later spokes without a fight or bending.
All the inners in, ready for outers