I believe that I previously posted some pics of my homemade push-thru die setup ... somewhere. But I want to point out a couple of more features.
The pushing rod has been center drilled. That does a couple of things 1) it applies more pressure to the edge of the bullet base, helping to square up the edge, and in the case of GC bullets, helping to seat the GC and 2) it allows the bullet to sit flat on the pushing rod even if the base has a sprue tit.
UPDATE: I now favor a solid pushing rod. It's less likely to damage coated PB bullets, and doesn't make much difference on GC bullets, especially since I switch to seating gas checks in a separate seating step prior to sizing.
The bullet is pushed clear to the top of the die. No need to wait for the next bullet to push the bullet all the way out.