I put a set of vented rotors and calipers from the w126 (1986-91) on my w123 300TD. They are larger than the stock units. The stock dust shields had to be tweaked to accept the larger rotors and calipers. I should have gotten a set to match the new brakes. The springs were also changed to the vogtlands in the front. Nothing was done to the rear at this time. I kept the Boge shocks as there was nothing wrong with them, and they are not a bad shock. I quite like the new feel, and it lowered the car, much to my liking also. Frankly, I'm stoked.