I have done this and it isn't that bad as long as you don't take the caliper apart. There are no seals that will hold once the caliper is taken apart. All you have to do is remove both pistons and clean with fine scotch brite and clean the inside of the cylinder as well. Then lube with brake fluid and press back together. You may want to replace the brake lines as well. Be careful when doing this so you get the line on correctly!!!! If not the line can rub the wheel and zap! no brakes!!
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