That advice is Only for vertical bush wishbones, i.e. Ford and not horizontal orientated bushes....ie Alfa.
You don't have to tighten the top wishbone bolt with the wheel on the ground... It defeats the object of how the arm moves... Obviously, otherwise the arm would never be able to rotate in its natural range of motion in the first place...
Torque up the bolt to the correct setting 48-52 nm and it should move up and down freely anyway. Then you fit the upper ball joint in.
If you have tightened the main bolt properly you should be able to still push the upper arm down to the hub hole for the ball joint easily.
The weight of the car settling on it isn't going to make the shadow of difference if you can actually perform this task by hand is it!
Come on guys, think about it
By what I can notice by the photos it looks like the coil spring has slipped out of the top cup and sitting against the lip alloy top mount instead. It usually happens when you settle the spring in the bottom of the cup of the shock absorber when it isn't straight towards you...Like having the hub turned on either full lock.
Take the wheel off and let the weight of the hub and leg hang down. Loosen off the upper mount bolts so it drops slightly. Don't loosen the damper main nut!
Slightly compress the spring and resettle it in its top mount. Cable tie through the top spring coil and over the top of the upper mount once in position. Remove the pressure off the spring compressors until it has settled on the shock absorber bottom cup and both are aligned.
Cut off the cable tie and jack up from the bottom wishbone until the top mount bolts come through the inner wing turret. Nip them up again. And remove the jack... Put the wheel on and low and behold no more gap that you can fit your head through