Biggest mistake is to think the screws will release from the get-go. If you try it that way, you'll only succeed in rounding out the screw heads with no hope of extracting them. Instead, heat the heck out of them from the beginning with a Mapp torch and make sure the screw head slots are cleaned out to give you maximum grip. Then hit them with the impact driver. If all else fails, drill out the heads with smallest bit you can, remove the doors and start treating the screws with penetrating oil, (Kroill, PB Blaster, etc ... Not WD40) followed by heat, then grab the stub with vise grips and pray. Otherwise, have fun drilling out the screw and re-tapping.