If it's the head, Sears has a tool for removing them without the old drill a hole - easy out method. I'd search Sears tools on "screw removal". I woudl not put a drill on this unit if it's not necessary.
If it's the thread - sometimes if you get all of the other screws out you can lift on the cover while turning the screw and this will help the good threads engage and extract the screw. This depends on the location and design, and is an alternative to Accent's razor blade method.
If it's the thread - sometimes if you get all of the other screws out you can lift on the cover while turning the screw and this will help the good threads engage and extract the screw. This depends on the location and design, and is an alternative to Accent's razor blade method.