noob wiring question
So I have a duplex in my dining room that looks like this:
It's behind a faux fireplace that I'm installing. I want to install a duplex and outlet in the outside surround of the fireplace shell, wired from this existing duplex location, removing the duplex in the process.
My plan: kill the power and run a new wire from this duplex location to the new outlet in the surround, installing a blank plate over the existing wall duplex with a hole drilled out of the center to hold the new romex.
Q: Can I simply twist together the 2 black hot leads (in the pic) with the new hot from the new romex in a single wire nut, and do the same for the white and gray? Obviously I'll extend the copper ground as well.
I told you it was a noob question.