3 Prong On Off Switch Wiring. You can install a ground wire from new three-prong receptacles back to the panel, or replace the wiring on the circuits completely using standard two-conductor-plus-ground cable. Especially if you have never seen one before or are just use to.
Simply adding an outlet with an additional prong will give you The power to the outlet being replaced is turned off at the service panel. Especially if you have never seen one before or are just use to. I have a lighted toggle switch that has three prongs on the back of it, but I am not sure what goes where.
If/when I find a solution that works, I will come back and post a wiring.
This will be confirmed at the outlet with a multimeter.
In place of that wire a ground strap or I'm removing an old dryer and replacing it with a new one. Always turn off the power to the circuit before working with exposed wires. Three-prong plugs are strictly for safety, and it's a good idea to upgrade to them.