Rear springs?

[DemonGT]

Long time ago i removed the whole rear of the car to have gears put in. When i reinstalled the rear end i swapped the LCA's
for weight jacker style arms.

I noticed when i was adjusting my rear ride height that each arm wasnt the same adjustment? Im wondering if i have bad spring
isolators on one side as i know i did not replace them. If i were to remove the stock springs in the rear to install new isolators
is there any reason to replace the stock springs since i can adjust the height with the LCA's? I already have Eibach springs in the
front.

On a similar note, i also have a annoying "creak" in the rear. When you push down on the back of the car it makes a "creak" when it
travels up and down. Im wondering if i tighten the LCA's with the suspension NOT loaded?

 

[Mustang5L5]

My adjustment isn't the same either.

There's a lot of variables that can contribute to that. Front springs not being exactly the same would translate to the rear. Years of body flex, and the fact that these are mass produced cars from 30 years ago, so tolerances weren't the best.