You *might be able to replace the upper cntl arm without removing the spring. A spring compressor would certainly make it safer. If you dont feel safe then have someone else do it. You def dont want to be hit with a spring.

Jack up the bottom a-arm to remove pressure from the top. Then remove the upper ball joint that is part of the upper control arm. you will need a tie rod end/ball joint puller to do this.

Leave the shock absorber attached as it will somewhat increase safety.

Then it is all fairly easy to remove and replace as a unit along with the other bushings for the torsion bar.

this link shows the parts and torque specs - even though the job listed is for the torsion bar. You can clearly see the parts involved.

https://cdn.w116.org/cd/Chassis/32-300.pdf

replace all the parts - if one is worn out then everything else is. Do both sides of the car.

for further help please join w116 dot org as there are more ppl there to help.