block the front wheels, raise rear of truck and support with jackstands on rear frame rails, use floor jack under diff to support while you loosen spring bolts, lower diff and replace springs installing the lower bolt and retainer first. Do not tighten up just yet, raise diff until top of spring is in place to install upper bolt and retainer. Rotate spring until ends of the spring are aligned in the retainer cups properly, tighten bolts. Install wheels, remove jackstands, tighten up all bolts to proper specs. Drive it for about 500 miles, re-torque spring bolts... Enjoy!