I did my breaks including the front calipers and it was not difficult at all, yes it was a little messy but you will be fine with some card board, rags and some break cleaner.
Oh and some good gloves too, yea, yea; some of you don't but I hate the grease in my finger nails after all these are hands are also instruments of love and pleasure (Barry White background music). <img src="/forums/images/graemlins/lol.gif" alt="" /> <img src="/forums/images/graemlins/lol.gif" alt="" /> <img src="/forums/images/graemlins/lol.gif" alt="" />

My rear left cylinder was leaking badly and the shoes were soacked completely. **See the before and after pics below**

For the fronts you have to remove the caliper and pump the break until the piston pups out (for this you will need something to collect the dripping oil), then clean everything thoroughly and using 1,000 grit sand paper and do the inside of the caliper and the piston.

You can use some water with the sand paper but make sure you dry the parts really good or use some kind of spirit to remove any oil or water spots to therefore prevent contamination.
Then, put the new seal in, rub some break oil inside the caliper and slide the piston in, DONE.

With the rear cylinder I used the same procedure and to install the O ring I as well rubbed some oil on it and it slided easily.

Oh yea, I painted everything so it look good. After all I probably spent about $30 which beats the $99 that some chains charge per side.

Pics:
Bad cylinder and the consequences:


After cylinder rebuilt


Javy