It's both but mine is an opinion

Here's how the job goes. It's from memory and it's been a few years so check your manual to be sure:

With the caliper out of the way, the rotor is clear for removal. Except, it's bolted to the hub and the bolt heads are on the side of the rotor you can't see. Pry off the grease cap at the center of the hub. Save the bent copper thingy pressed into the center of the spindle. Loosen the bolt pinching the ends of the nut clamp at the end of the spindle. Spin the nut clamp off the spindle. Gently wiggle the rotor and hub on the spindle to loosen the washer and outer bearing roller set. Remove the washer and outer bearing roller set. Pull the rotor and hub off the spindle minding the inner bearing roller set -- it'll likely stay with the hub because of the grease seal but who knows if the grease seal is still intact. Release the rotor from the hub by removing the five bolts holding the rotor to the hub. This is one of the worst jobs I've done on an MB.

Installation is the reverse of removal EXCEPT you have to set bearing preload. Also, if the bearings haven't been repacked in a while, they'll be coated in gray clay rather than green grease. It's up to you to put things back the way they are or give the bearings a good cleaning, inspection and repacking. Whatever you decide, you have to set bearing preload properly or at least close to properly so you don't burn the bearings driving the car to your mechanic. It's not difficult to set preload by feel even without a dial gauge but there's lots of debate whether that's an acceptable method. Lots of mechanics do it by feel but they've done it hundreds of times vs my handful of times and your first time

This assumes Ferdman doesn't in fact know how to remove the rotor without removing the hub. If he knows that secret and is willing to share, everything I wrote means nothing.

Sixto
87 300D