Wish I had a working scanner, could send you or post the manual pages on this. Pretty much jack up the truck, Block the front wheels, and back wheels to keep axle from moving. Place jack stands at rear on frame, not under axle.
. Spray all the u-bolts on axle with PB Blaster after wire brushing. Spray the bolts at the trailing arm bushing and the drive shaft u joint bolts if you plan to remove this. I'd just put something under to hold up the front at the axle. Unclip the brake lines and parking brake cables from the trailing arms. Then remove axle u-bolts and bushing bolts at front of trailing arms.
That should be it. Put back in and retorque. Good luck. Jim