There are only a few ways to remove badly stripped screws if you cannot use pliers. None of them are pretty.
1) Take a dremel with a cutting wheel and cut a line into the screw head. Essentially you are trying to create a cut in the head so that a slotted screwdriver can be used to remove the screw.
2) Use your drill and drill down into the screw. This weakens the head so that you can bust the screw head off and it also cores out the post. If you're extremely skilled you can use a tap n' die set to correct the post afterwards, but for small screws you'll most likely have to replace parts.
3) Cut the top of the screw head off with a mini hand saw. This is dependent on how much space you have available to you. If you can't cut the head off using flush cutters then you probably don't have the space.
Option 1 is probably your best bet. Just protect everything as the grinding will make a mess. Use steady hands.
Another option might be to remove the entire PF and access it from the side? I've never removed the PF before though so I don't know if this is possible.