Doug,
Guessing that you have the truck supported on jack stands under the frame.
Once you place a jack under the axle to unload the weight off the springs to unbolt everything, maybe use a couple ratchet straps hung over the frame rails and supporting the axle to keep it in place and not stress brake lines/hoses and such as mentioned before unbolting the springs and hangers.
Safety 1st as the saying goes.
Dan
