I got round to fitting new front discs & pads on my x type 2.0d (54 plate) as it was an advisory on the MOT, (inside of discs are ribbed) so after removing wheel and caliper, plus the discs I got down to cleaning the caliper and stripping off rust with my dremel with diamond tip attachments, also with a grinding tool attachment too, which taken hours to do! then a can of brake cleaner, which cleaned off dust. then cans of spray paint to give a nice new look on the calipers... but patience pays off ? then it was on to fitting the new disc and doing a "run out" test with a dial gauge. the max of run out with new disc is 0.15mm...... mine ran out to 0.05mm to 0.08mm and was the same for both sides. happy with the results of the run out test I then started to fit everything back...many other checks were done too, besides of new brake fliud, piston inspection and movement, sleeve seals, and all rubber boots. here are some photos....enjoy :-)