how about mk3 mondeo calipers and focus st170 300mm discs, as with a little light reshaping of the outer edge of the caliper and re drilling the hub bolt holes out the fit behind 15" wheels, its a common conversion on the zetec s mk5 fiesta. I ve fitted this conversion apart from the caliper mods to my girlfriends mk6 zetec s fez as it running cossie wheels and it throws you into the seat belts well when you brake hard.