This is what I did on a 66 T-bird about 20 yrs ago.. it had 4 piston calipers on it, and when they needed to restored.. found they were seized up. They were two piece units, so I took them apart, put one half off caliper in the vise, heated the caliper (outside on caliper bore with a torch) be careful when doing this as it can, and you can/could start to melt the cast iron. After you think it is medium hot, get some dry ice and stick some inside the piston puck.. and what I did was take a very large pair of channel locks, (and slid over 2 pieces of heater hose or fuel hose, 5/8" or 3/4" whatever fits snug on the teeth, and work piston back and forth, and you should be able to rotate the puck to come out of the bore, if not.. try again. Before, these steps,it helps to remove the old dust boot with a razor blade. Of course if the piston is below the caliper housing bore edge.. you may have to see about hooking up to another hydraulic source to see if it will break loose. Hope this helps.
