Im sure mondeo 300mm calipers fit straight onto non focus ST knuckles you may have to drill the caliper mounting hole by 2mm but thats it. ST170 calipers have a seperate carrier that bolts to the ST170 knuckle, the mondeo does not, the caliper bolts straight to the knuckle.
So you need MK3 mondeo calipers and pads, ST170 disks.