EDIT: I hope Volvo didn't intentionally design the fuel door as a break away from the sheet metal of the body
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OEM coarse screws stripped hole in sheet metal.
Found some nuts and bolts in the tackle box of misc fasteners.
Enlarged the holes in the hinge and sheet metal, used magnet as handle with cardboard for backing (not pictured) to wedge the nut firmly against sheet metal as the screw was very short. The width of the gap in the body was wide enough for any combo wrench to hold the nut for tightening.
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