I read this thread at the weekend and had a go but the problem was I had a poorly very smokey turbo, so could not tell if I was going too far.
I turned the screw 2 full turns, the diaphram from 9 - 11 oclock, and the star wheel 90 deg.
I did notice some improvement so I left it at that.
I have a boost gauge and I was getting about 0.8 bar.
Last night I fitted a replacement turbo, and before I did I wound the actuator bar up by 3 full turns.
Coming home afterwards the truck seems much smoother, easier to drive and I was getting about 1.1 bar boost.
I have just set the diaphram to 1 oclock and moved the wheel to 180 deg, took it up the road and no excess smoke, but will report back when I go out later for a longer drive.
I am so glad I found this thread.