u could always cut up sum garden hose and slap it on the bottom part of the spring. on the top, there is a rubber plate that fits onto the spring.

so am i to beleive that when your car is on the ground (not jakked up) and the full weight is on the suspension. you can move the spring around???

seems like your strut might not be compressing and that would be taking all the weight from that corner of the car.

are the rubber bushings on both sides of the mounting plate??
go check both sides, and make sure they look the same from inside your trunk (from the top).

my springs didnt quite fit on the perch, the opening on the spring is too small, so i just lined it up as good as i could.

anyways, when doin my springs, i noticed the strut has extra play in it with the piston that goes inside the phat part. like it can come out farther than the spring assembly, and i could push it in, making it too small to fit the top bolt and mounting plate on the strut assembly.

to swap out the rears, its only 3 bolts, the two in the trunk, and one goin through the bottom of the strut. not really that hard if u wanna compare the diff between your good one and "bad" one.

corbin has an exellent writeup

hope that made sense