W203 270cdi brakes on W124 XXX
W203 270cdi brakes on W124 XXX
Most calipers bolt to most hubs, the problem is that either the caliper or the disc has the wrong offset for the combination, so yo ucan either space the caliper, or easier usually, just get the discs from your particular car that has the correct offset for your bigger caliper, usualy from the bigger engined model car.
Regarding brake hoses, just get hoses made up with a banjo fitting on the caliper end, and add 50mm to the original hose length.