Greg, I got this.(formerly from the land of the rusty cars)
What needs to happen is clean the axle center register if you haven't already,lube with PB or similar,and pull OUT on the drum outer edges, even if only with a couple of pry bars,(no need for the 'force of God', just some tension)
and use a punch and a small sledge to knock the axle center register IN at the same time.These axles have(or used to)a good bit of end play, and if you "unload' it by prying the drum OUT, and knocking the axle IN simultaneously, it will give.Trust me.
regards,your new neighbor, Case