PoCo Guide

Guide on how to make a Pocket Color using Natalie the Nerd's PoCo kit


While this is an easier method to build a Pocket Color, it is still a challenging project and you will need to be confident in your soldering skills.

By purchasing this kit, you are accepting all risks, costs and acknowledging that I (Natalie the Nerd) am not obligated to provide support or troubleshooting. I am not at fault if you ruin your Game Boy. 

Parts and tools

What's included:

Poco board

Pre populated poco 1:1 board
** not including the DC board, DC jack and headphone jack

Poco flex board

Flex pcb that lines up with the poco and the vias on a Game Boy Color. NOTE: CPU E boards are not compatible with the flex.

Pocket battery contacts

Tools and resources you need:

- Game Boy Color in working condition
- Soldering iron
- Wire
- Desolder wick or pump
- Kapton/polyimide tape
- A dremel or craft knife
- Game Boy Pocket shell (preferably FunnyPlaying)
- Game Boy Color screen (OSD)

The cut

You will need:

Either a dremel or a craft knife. The dremel cut is self explanatory, the craft knife method is done by scoring and snapping the PCB. This method is used to cut acrylic. Please watch videos on youtube to make yourself familiar with it.

NOTE: proceed at your own risk. Once again, all risks are taken on by you by following this tutorial. I am not liable for any mistakes

The cut needs to be done right under the cart slot. It is easier to cut from the front. A good guide is to draw a line right under the notches of the cart slot as shown. 

Preparing the poco board

The DC jack, headphone jack and DC board need to be moved from the GBC bottom you just cut to the poco board.

You can now also remove the power LED now as it wont fit in the shell.

Moving the switch

The power switch on the top half of the Game Boy Color needs to be moved. Desolder the IR LEDs, Q3 and the power switch. Don't forget to clean the power switch contacts! Use desolder wick to clean the access solder from the IR LED pads. This area needs to be as flat and clean as possible.

Trim or sand the two small stand offs on the bottom of the switch to make it flat/

Cut the [GBC Switch] board off the flex PCB. Solder the switch onto this pcb and use the adhesive on the back to place it on the top right corner as shown.

Next, solder wires from the switch flex PCB C and 3 pads to the C and 3 pads where the power switch originally was.

Flex PCB

WARNING: The flex is very VERY delicate.

The vias on the front of the Game Boy Color board need to be tinned in preperation for the flex PCB. If you are having trouble soldering to the vias, please watch this video.

Tin the vias in the image bellow. You want to fill the vias with solder like cannoli - not just on top like a cupcake.

Once they are tinned, align the flex with those tinned vias and solder all the joints. Adding a touch of flux can be helpful but it is not necessary. Don't forget to solder the ground pad to the cart pin as shown above. 

Flip both boards over and align the pads from the flex to the poco bottom. Please note the placement of the flex in regards to the pads and the top battery contact. Solder the flex to the pads.

Place kapton tape over these joints to insulate and strengthen them. You must at LEAST do this to the joints on the left as the battery contact will touch this area.


For the easiest install, use a GBC OSD display. These displays have an onscreen display which lets you move the screen to fit into the correct area. I also recommend Funny Playing pocket shells as they require zero trimming.

Make sure to install the OSD screen wires.

Screen link and installation instructions

PLEASE test the screen and the device out of the shell first