Don't have to remove the brake lines + that wouldn't work anyway. jack the car up and use a jack stand to support the axle opposte the side you are working on. use a floor jack and position it under the rear of the lower control arm and loosen the bolt( might have to jack it up a hair to remove the bolt) and then slowly lower the jack down the spring will unload and fall out. leave the rear shock connected this helps hold the rearend in place. install the new spring, jack the arm back up and reinstall the bolt and torque to specs and do the same for the otherside.