A friend has an old muzzleloader that I've offered to refurbish for him. It's not a shooter, just something he want dressed up to hang over his fireplace. Trouble is, two screws are solidly frozen, and I need to remove them to do a good job. The first is the tang screw, the other is a side plate screw. Both were buggered up by a previous owner. I've tried Kroil but that hasn't seemed to help. I can't get a good bite with my screwdriver because of the bad screwheads. Any suggestions?