With the weight off the rear end, you should be able to pry on various portions of the trailing arms close to the bushings and notice if there is excessive play. If your trailing arm bushings are bad, you'll need a special tool to take them out and press them back in. The torque arm can easily be taken out and the bushings pressed in and out. Have replaced shocks, struts, u-joints, trannie mount and center support bearing on driveshaft, and some front bushings. Trannie output bushing and pinion bushing have no play.
Wheel bearings are good.
Nothing is rolling around in rear of car or spare tire well. I would focus on the rear suspension bushings. I would suspect the subframe mounts, probably got accelerated wear from soft torque rod bushings. The Haynes manual is adequate for procedures here. Of course you should first check for loose upper or lower shock mounts or loose sway bar mounts.