I'm replacing the brake disks and pads on my 2013 E250 Coupe. I did the fronts no problem and had intended to do the rears last weekend, however the upper caliper mounting bolt is obscured by a vertical tie bar of some sort, and clearance is limited such that you can't get a 37mm long 18mm 1/2" drive socket onto the bolt head. I've considered buying a shallower 3/8" socket but I doubt that there will be room left to accommodate a ratchet on top. Of course I realise that I could utilise a ring spanner and a hammer. But does anyone else have a more elegant solution?