Considering the age and value of the car, I would suggest putting in new springs and a new spring at the swing arm. The 113 was not a true independent rear suspension. The differential and left axle are bolted to the frame, and the right axle swings up and down. the right axle changes length depending on position by means of a sliding joint. The sliding joint is the Achilles heal in that suspension. There is a spring attached to the back of the diff that holds the back end up. I'd replace that first with new pads. If you go for new rear springs, you will need to order them first. When you get them, note the color and number of paint stripes and order the rubber pads with the correct # of burls to match the springs. Your ride height should be perfect. Although I don't see a need, you can adjust the lower spring perch. You drop the control arm, remove the spring, unbolt the lower perch, and rotate it. I just described the procedure, but it is not that simple. IF YOU DON'T KNOW WHAT YOU ARE DOING YOU CAN BE SERIOUSLY INJURED OR KILLED IF YOU LOSE CONTROL OF THAT SPRING. Please heed this advice.
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