Don't forget the fronts have a spindle Nut.
I have had this same problem. Banging, pulling, sticking various objects in from the back, levering and so on. You have to figure it's ok to damage all insides because you are replacing it all. The drum has "rusted/corroded" onto the shoes. It will come loose in time... a little at a time. If you can get to just a little of the shoe, bang it inward hard with a blunt chisel or other. Some folks use heat, some folks drill a hole in the drum to poke into. If you do have movement as TC says (either rocking or rotation), then it's more of a gentle attack and the hub may be stuck instead of shoes.
