A few years ago I had a TT with two (2) slides, one the living area and the other the dinette area. Neither had electrical outlets. I added two (2) 120vAC outlets with USB outlets built in to both slides. I used shallow surface mount boxes and wire conduit running from the floor up to the boxes. I placed the boxes higher than normal so I wouldn't have to bend over to reach them. I tapped into a 120vAC line I found under the TT, ran 14/2 with ground flexible cord following the 12vDC wires for the light in the slides. By following the 12vDC wires that gave plenty of room for the new wiring to flex when the slides moved. This set up worked well for us.