Keep in mind, I hate electricity and electricity hates me. It's a relationship that goes waaaaay back to childhood.
I wired our new house, and all the figuring required for that, which is not much, mostly just very basic stuff. Something learned was to not trust my memory on whether the breaker to the circuit being worked on was indeed off and never, UNDER ANY CIRCUMSTANCES, pee on an electric fence. Trust me on that one. Seriously, never ever do it. Not even to a drunk buddy. Other than that, I know about as much about electronics as my dog does rocket ships.
There is likely to be some smoke, maybe fire, but hopefully no electrocutions.
Basic sheet of aluminum which just so happens to be the same thickness as a tablesaw blade. You'll see why later.
Drilling holes for the transformer, wires, tube sockets, phone plugs, etc.
And the reason for the aluminum sheet being the same thickness as a saw blade. For the bottom and sides I cut a few pieces of scrap to ~3" x whatever length it took to fit around the metal sheet then cut a groove in the board for the sheet to slide in. Figuring this project may be dissembled many times during the build, and facilitating my clumsy hands and soldering ability, the ends are simply held in place by screws. Not pretty, but unscrew one end and the metal sheet holding everything slides out making things easier to work on.