One silly question here.
If the revised settings from wim have been worked out as the settings to use ,is this to allow for settling of springs etc as the cars age or is it because Vauxhall’s original settings (even if in middle of allowable range)were totally wrong to start with?.
If it’s just to allow for settling then what is recommended if car is at proper height.ie new springs etc.original gm settings or wim settings ?
Set a car up perfect once.
Measure the settings with the car loaded and on the deck. Record the settings as a base.
Lift the car at one end.
Remeasure the geometry and record as setting.
Repeat for rear.
Set next car with wheels off the deck.
Set onto deck and cross check against original car.
Tweak as required.
Using computer driven gear is really handy for this as you can set all four wheels to spot on, even if they have no weight on them.