Re: Suggestions for removing seized cover bolts??
The impact driver suggestion is the best idea. In a pinch, and if you have a helper cause it takes at least three hands, try tapping on the screwdriver with a hammer while turning it. If you have a screwdriver with a square shank you can put a crescent wrench on the driver which will give you a little more torque while leaning into the screw. It's critical that the driver fits the screw. Too small/thin and you'll strip out the slots.
I'd invest in the impact driver. They aren't that expensive and a good tool to have around for stubborn fasteners. Or an impact wrench, electric or pneumatic.
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