What does the service manual say?

Order two sets of Moog upper Control Arm bushings Part Number K7103

Yes you have to release the torsion bar tension.

Just put your floor jack under the ball joint in the lower control arm, and put some pumps of the jack to put some tension on the suspension.
Then just smack the upper ball joint loose, by any method of your choosing.
Remove upper control arm.

Don't have one.

The moog offsets have to be installed opposite of directions that comes with them.Rocky

No. Use CNXT's instructions, which are NOT opposite of Moog's instructions.

What are CNXT's instructions? I'm not familiar with them.

Look up 5 posts, not counting this one

Be aware that those K7103 bushings, installed in an e-body, may reduce your adjustability. I had the exact same set up and found I could not rotate the alignment cams a full 360 degrees. I found that the edges of the upper control arms hit the fenderwell or control arm frame between 2 o'clock and 5 o'clock position on the cam. And I found the adjustment nuts for the bolts really had to be wailed on to keep the alignment settings in place - so much so that I ended up stripping the threads out of a few nuts. You may also hear all sorts of creaking and groaning from those bushings, due to the more extreme angles you can get with those bushings. I found the press on washers that come with those bushings tended to want to pop right off when I removed those arms with those K7103 bushings. Some aftermarket alignment cam maker offers longer locking nuts (close to an inch long) that would solve the thread issue. The next time I try those offset bushings I am going to run the lower ball joint spacers as well, to see if I can get the alignment numbers I want without having to crank the alignment cams so far that they foul on the fenderwell or control arm mounting frame.