One tip is to take a measurement of the center of the spindle at the ride height before you take everything apart. I use the wheel well lip directly above the spindle as a reference point
It took some fiddling around for me until I realized that had to happen first.
I actual left the shock on, but unloaded the torsion bar by backing off the adjustment bolt. I did carefully measure and record the number of turns it took to back off the bolt.
I moved everything up and down with a jack. It gave me precise control and the shock kept things partially loaded.
I use a white grease pencil to write those measurements on the car. Ride height measurements on fender and torsion bar measure on the LCA.