I have always been under the impression that this method only works on pan cars because 4WD touring cars don't have a solid rear axle.... but maybe its changed... I do know a tweak board will be much more accurate

doing it with droop screws would be definitly less than the best way to do it... droop has a much greater effect on a car's handling and the way each wheel grips more than most people relise and I definitly wouldn't recommend using... at worst you can use shock tension in a squeeze