On screwing back in the pistons of the rear brake calipers: You can "make" the 12mm-hex key out of a 12mm-head bolt and one or more of its nuts. You screw the nuts on, put the head of the bolt into the piston hole, and use the regular socket (around the nuts) to turn the whole contraption. Jakov 82 Coupe 86 5000 TQ wagon