I just did my rear brakes a couple of months ago. Once you figure out how the piston moves back into the caliper, this job is cake. <img src="/forums/images/graemlins/kewl.gif" alt="" />

As the other poster mentioned, grab the piston in the divots with a pair of needle nose pliers. Twist (clockwise, I think, but I'm not sure) until the piston has receded enough to allow the caliper to seat on the post and slide over the rotor and pads. It'll take some time, and the piston is very hard to turn at first, but it will get easier, and it will move back into the caliper. Have patience, relax, and it'll go fine. <img src="/forums/images/graemlins/cheers.gif" alt="" />

And remember to take it easy for a while after you get it put back together so that the pads have time to bed in. No panic stops if you can avoid 'em. Or you may end up <img src="/forums/images/graemlins/shiner.gif" alt="" /> And remember that it's normal for the pedal to feel awkward for the first few uses after you do this job.

Good luck! <img src="/forums/images/graemlins/smile.gif" alt="" />