I take the FL sizing die apart, cram a paper towel up into the body with something small like the decapping pin and rod that I just removed, and twist the paper towel a couple of times then pull it out. This gets out most of the excess lube and carbon inside the die, and I wipe down the decapping pin and rod with the same paper towel. Works well, leaves a bit of lube up in there, and doesn't require any solvent or abrasives or brushes. I have a single stage press, so I don't have to deal with some of the additional dies on a progressive.