I had the same problem on my rear brakes. After replacing the rotors and barely getting the pads in i realized that it was so seized up that the rotors werent turning with the pads in.
Instead of removing the caliper completely, get a torch and a wrench. Remove the rubber boot with a wire and a flat screwdriver. Heat the caliper where the pin enters and turn the pin back and forth until it starts to move freely. When it can rotate, clamp a vise-grip on the pin and while turning the pin hit the vise-grip with a hammer until the pin comes out.
Drop the pin in some water, clean off with a wire brush and lubricate it and put the boot on and youre good to go.
you dont need to remove the caliper which saves you the job of bleeding the brakes.