You do not need to remove the caliper. I just replaced my pads last month and it was the easiest pad replacement I have ever done. You simply remove the small cotter pin and punch the pin that is holding the pads in place. If you go to rennlist or view the following youtube video you will see what I mean. The video is for a boxter barke replacement but the procedure is exactly the same for a 997.2
Porsche Boxster Brake Pad Replacement - YouTube