I started the project by carefully gutting the viewers and bagging the parts based on their serial numbers for future reference. I wanted to use the viewer's built in on/off switch, so I cut the power supply cable and soldered it to the switch. The micro USB end goes into the Pi Zero.

These are the parts used for the project. They are described in the components section.

You can purchase the Pi Zero with headers to plug into the TFT touchscreen. I found that out later, so I purchased the solderless hammer headers. As the name implies, you have to use a guide and a hammer to correctly insert the header into the Pi. It saves time unless you enjoy soldering 40 pins.

The screen comes with two sets of headers (the second is a pass through header). This is a good time to insert your RetroPi operating system using your micro SD card.

The amazing thing about this combination of Viewlex viewer, 2.8" TFT screen and Pi Zero is that they fit together like a glove. Once you put them all together, the screen and Pi slide onto the old hardware and the top case keeps them all nice and tight without any other securing hardware. On some other models (the gray ones in the main photos), I had to remove the bottom two buttons from the screen to fit the frame and cut three of the lower pass through header pins that remain exposed to fit in straight.

But first, add some electrical tape on the bare metal frame of the Viewlex and on the exposed solder points on the screen and Pi. I overcooked a Pi Zero - static electricity shorted it because I didn't use electrical tape to isolate the solder points.

Once you have all the key ingredients, it is time to bake your Pi. Plug in your power cable, the four port USB hub, the game controller, USB speaker and put the lid on it.