adjusting brake pedal push rod?

Always start in the back, and adjust until the brakes jam up. Then go pump the brake pedal to center the shoes. Then go jam up the shoes some more. And then go pump the pedal again to, as before, center the shoes and starwheels. Now loosen the starwheels just enough that the wheels will turn; a lil rubbing is fine. The drums are not likely to be round nor free of taper, so some rubbing is fine. That's how I do it, to get a hard pedal.
Now go do the fronts the same way, but here I don't allow quite as much drag.
This should all but eliminate your dead pedal. Some deadness has to be there to endure your master-cylinder piston retracts all the way, to ensure the Compensating Port remains open.
On an all-drum M/C the pushrod is captured in the back of the piston, and so that end is not supposed to have any play in it. If yours does have play there, you can figure out a way to eliminate it, but remember; when yur done, the C-port has to allow the fluid to return to the reservoir.