reove wheel, undo 12mm bolts holding disc on, undo bolt holding caliper on and 8mm nuts securing brake pipes so caliper can be slid off top anchor and put out of the way, remove pads. to remove disc you need to remove caliper housing. these are 10mm or 12mm(?) allen key bolts which are very very tight and a big breaker bar lots of force will be required to loosen them. disc should then come off. replace disc, caliper housing and fit new pads, push back pistons and refit caliper. job done.
me, April 2010