I just did my pads on rear of E350 (06) and I thought also that after removing the caliper (18 metric)it was just the screw and bang the rotors off. With 3/4 back plate there wasn't a lot of banging room. Even a torch around the hub didn't do anything. should have thought ahead before the job,.... what if they don't come off. (OTC rotor puller?).
Result I left the rotors on and carved the pads where the rotor edges showed. The rotors were in good shape to begin with. Used OEM pads and wish I would have used anti squeak paste. Rotors didn't warp during torch process. Is there any store that rents those rotor pullers. By the way auto zone had the rental tool for the piston. Pay up front and got money back after couple days.(works ton better than C-clamp). Being a Mom doing just pads.