My plan for the Bottomless Pit piece was to have the screen/box combo sit on top of another cardboard box. Problem is, the weight of the screen would likely cause the box beneath it to cave in. I decided to buy a table to act as the interior support. I’ll cover the table with the lower box.
In order for this to look seamless, I drilled holes in the table so that the power and HDMI cords could feed up to the screen through the bottom box. Success!