PREP
1) Loosen all rear lug nuts
2) Chock front wheels
3) Jack up car (I suggest under rear A-arms) and use axle stands (I suggest under rear suspension assembly / cross-member). Get it as high as you can.
4) Remove rear wheels.
5) Give all fittings (caliper bolts, p-brake cable ends) a shot of penetrant. Don't use WD40; PB Blaster is my potion of choice.
6) Go inside. Make tea; start a repair thread.
More to follow.