Well I was considering using 1x1" wood strips to make a channel (the
wires between 2 strips of wood, maybe 2" apart), possibly even covering
it with a thin ply or something, I bet I can get a whole load out of a
4x8 sheet of thin ply.

You see, I want to expand in the future and possibly add some 20 amp
outlets, generator outlets, etc. I saw the expandable enameled metal
boxes, but they are big $$$$$.

Dean