The Lee sizing dies are push-through that attach to your press (7/8-14 thread bodies). The tool is super simple, just forcing a lead slug through a steel tube basically. I have enlarged a couple Lee sizing dies with a wooden dowel, split an inch or so and a piece of emery cloth wound around the dowel. Place the dowel in a drill, oil the emery, and insert into the die. Turn the drill slowly and check often...