Any other ideas other than drilling? -- Yeah, get yourself an air compressor, an impact wrench and appropriate sockets and have at those screws. They should come out very nicely. Alternatively there is an impact screw driver available, check with your local Home Despot or other good tool store. You can also heat the things with a small torch to break the bonds the bind and then turn them out as usual. If you go the compressor way, get your face shield, your coveralls, your ear proctors, your thigh boots, leather gloves, Kevlar vest and your construction hat. Just to make sure and impress your customer. Newton (with tongue in cheek)
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