the bolts that have to be torqued when it is on the ground are the following:
Trailing Arms (they are the fore/aft links), Front and rear bolt
Radius Arms (the ones going cross car): the center two bolts
The outboard radius arm ones can be torqued in the air (they are through heim joints so they'll rotate fine after torquing). The ones that must be torqued when on the ground are through rubber bushings, which will be clamped in that position and if they are torqued while the suspension is hanging down will be twisted too much on the road and wear out too fast.
One work around, if you only have a jack and not a work pit:
1) Measure the normal ride height (measure from the bottom of the rear knuckle to the flange on the rear subframe.
2) jack the car up as high as you can go. Support it by jack stands so the whole rear suspension hangs free.
3) Use the jack to raise up one side of the suspension until it is around its normal ride height that you measured in step 1. Have a friend sit in the car, or put a lot of ballast in the trunk, to help compress the spring on that side.
4) with the rear suspension held in its normal ride height, crawl underneath and torque those remaining bolts.
5) repeat on the other side