If you are even a gimp at using a drill then drilling the heads off is going to be the easiest way, just be careful not to drill into the carburetor itself and all is good. The screws aren't likely stuck, or seized, they are just TIGHT. Machine installed tight. When you drill the heads off, and then remove the rest of the screw with you fingers, you'll know that the threads are not seized. The drill trick should take no more than 5 minutes or so. On my first quad I used a dremel to make a slot for a large slotted driver - that worked but man drilling them out was sooooooooo easy on the second one.