I use a piece of 1/2 inch allthread and some washers to compress the springs, just enough to get the lower control arm bushings pinned on with the bolts.
Put allthread , (about an 18 inch piece) through the hole where the shoch absorber goes through. and at the top where it goes through the spring perch (bucket for spring)
I put 2 nuts on top end and tighten them together , then put a couple hefty washers on the bottom. Then you crank the bottom nuts down to compress the spring. Usually only a few inches is enough to get the bushing ends of the control arms close enough to slide the bolts in.
Once you have pinned the comtrol arm at the bushing end, lift the car by the ball joint end of the control arm, using the cars weight to compress the spring further so you can hang the spindle.
Once you have the spindle back on THEN remove the allthread. In case you slip before you get her coupled together, the allthread keeps the spring from flying out if things get hairy.
ALSO .. very important.. many guys make this mistake....
Dont tighten the control arm bushing bolts untill last. You need to have the car setting on its weight on the ground so the bushing is registered in the position it will be in with the car on the ground.If you dont, the center will rip out of the bushing and it will groan and creak like an arthritic old man and you wont like that, I assure you.
Fact is stranger than Fiction