How do you get the old shower base out? We're remodeling our bathroom and changing the configuration of the stand-alone shower, and need to pull out the old base and replace it with a new one. The green drywall is right on top of the flange. I've cut a little off (about 2 inches) to give me some room, but I still cannot lift the base up enough to make it clear the drain stack. Should I simply remove the drywall high enough to be able to lift the pan, or is there a better way? Thanks.