With yours being an 04 the springs are listed the same from 03 MY both for the 4200 and GS. Same goes for the anti-roll bar diameters.
So all they did with the GS is wind it down a little, and fit the 19 inch wheels of course.
Can't comment on whether the geo was changed though.
I'll also look at GS overall tyre radius vs. 4200 and if they are the same, may well just have the car set to GS settings (assuming different).
Chris
I plan for the car to stay standard!
Chris
I did my geometry at Christchurch tyres, very knowledgeable and the results are worth it.
Im gonna do mine soon too . But will probably get the geo done and lowered to GS spec . Where s the best place south of london ?
Emblem, end of.
They have their own modified GS spec which is brilliant and does not wear the inner edges of the front tyres.
Smile nicely and your looking at £200
Emblem don't do it themselves, they have a local guy, so if anybody on here knows who it is you might be able to book direct.I need Emblem to do mine before my track weekend in a few weeks time. But they're closed for their summer hols, so can't even book it in!