I heated around the outside of the drum with an acetylene torch, removed the bolts on the wheel cylinder and rotated the cylinder inside the backing. then I attached the wheel ring back on with a couple of studs (not the whole wheel, just the little donut shaped peice) and used a 4 foot 1 inch solid steel pry bar to move it all around.
took about 2 days, and 3 heatings (not to red hot, just make it hotter than the rest of the truck) expansion will break the rust bond.
since the axle is out fo the truck, you may want to pin it down with something really heavy while you futz with it. so that all your force is going into the drum and not into wobbling the axle about.
-Mike R.
