Couple of tips:
I use the ht2 spanner to hold the cup when knocking out the bearings: open workbench or vice until its just wider than the cup, rest the spanner on it and then sit the cup on the spanner. Lightly clamp the other end of the spanner. Stops things sliding around when knocking the bearings out (which come out very easily IME)
A headset press really isnt necessary to replace the bearings. Before installing the cups in the frame, gently tap a bearing into the cup a bit, then use a vice to squeeze it in (it’ll go in straight like that) and use the old bearing as well in the vice to squeeze it in the last bit so you dont mash the cup.
I’ve done this half a dozen times now and it really is a ten minute job (not a ten minute job that takes two hours!)