The original screws are clutch head and the top ones are usually rusty from the windshield gasket leaking which ALL screw out windshields do. On a 41 and 46 that we pulled the dashes from we found if you used a very small torch tip like an 0 or 00 and heated the screws they would usually turn loose and no surrounding metal would be effected. While the dash was out you can restore the instruments and rewire everything(the guages, switches, ignition, etc) and not have to stand on your head doing them, just leave the wires extra long and trim to length later.
