I have recently bought an older 60's home. There are only 2-wire receptacles throughout the home. I wish to ground some of these receptacles, especially in my workshop and maybe add some exterior outlets. A friend told me to just replace the old 2-wire outlets with new grounded ones and just jump a piece of copper wire from the ground screw to the neutral screw on the new outlet and it would be grounded. Is this true, or should I replace the old outlet with a GFCI until I can get the place rewired?