Often, coil springs can be crammed into place with a floor jack...if the front axle of the floor jack is chained to the frame of the vehicle so the jack will lift the control arm into place without lifting the entire vehicle. Yeah, it can be tricky.replacing the A-arms on my 90 c1500 did not fair to well just using a floor jack. I had to go rent a spring compressor from my local Advance Auto.
If the control arm has bonded-rubber control arm bushings, those bushings need to be torqued at normal ride-height (weight on the suspension.)alldata for my Saturn, it mentions torquing everything for the front strut assemblies with car jacked up.
If the control arm bushings are Polyurethane, or Delrin, or whatever-non-bonded, they can be torqued in any position.