Loosen the rear wheel lug nuts, raise the vehicle, and support it securely on jackstands placed underneath the frame before removing the wheels. Support the rear axle assembly with a floor jack placed underneath the differential. Disconnect the lower ends of the shock absorbers from the axle. Disconnect the driveshaft from the rear axle and hang it with a piece of wire from the underbody. Remove the rear drum brake assemblies or the rear brake calipers and discs, then disconnect the parking brake cables from the parking brake levers or the parking brake shoes. Detach the brake junction block and all brake line clips from the axle tube, ensuring to also disconnect the breather hose from the top of the differential housing. Support the rear axle assembly with a jack, then remove the U-bolt nuts from the leaf spring seats and raise the axle assembly slightly with the jack. Remove the rear spring shackle bolts and lower the rear of each leaf spring to the floor, carefully lowering the axle assembly to the floor with the jack before removing it from under the vehicle, ideally with the help of an assistant due to the weight. Installation is the reverse of removal, ensuring to tighten all fasteners to the specified torque and the wheel lug nuts as well. Finally, bleed the brakes.