I was a Mercedes mechanic. I changed the rotors by removing the wheels and then removing the big bolts holding the calipers, swing them out of the way, then the small bolt in the hub. Next I had to rotate the rotor and wack it real good in several places from behind with a heavy hammer due to some rust at the hub. I always use jack stands. I made the mistake of using aftermarket rotors and got vibration during braking from warping after a few years. Went back to dealer ones and they have been fine.