As far as im aware, the easiest way is to put a couple of coil spring compressors on to the coil spring on one side, compress the coils to take up the tension, then out a jack under the rear arm to take the full load, then release the lower shocker mount bolt, then lower the jack until the coil spring slips out. do the same in reverse to fit new coil. then do same on other side.
Please don't attempt without compressors, or the coils spring will still be under tension when you lower the jack down !!