Require less than 30 minutes and some very common tools:
Plastic Glue or SuperGlue
So let's go
Open the game boy, remove pcb and screen and take the back part.
Use the plier to cut parts in red square.
Width of the game boy (first generation) is exactly the width of Rpi.
Enlarge Ext.Connector and Vol holes on both side with the plier. Adjust with the Cutter
Same thing on the upper side
We have to enlarge left side too, for power supply and SD socket.
Now glue buttons and pad.
Close the case with screws that still fit (at least the two inside battery box)
Et voilà :
- HDMI connector on the top of the gb
- Video and Sound on the bottom
- Usb hub ?