looks like you've already got the track rod ends in that pic! Unless they need replacing, when they need to be S3 ones and not just mk4 ones of course.
What are you doing about the ARB? your current ARB will no longer bolt up to the wishbones.
Do you have ARB tabs on your front struts / coilovers? Ideally you'll need an S3 front ARB and drop links as well.
parts wise, you shouldn't need much else, steering rack connections are a straight swap over, perhaps new subframe bolts, and PSF but that's about it