How to remove the back housing of the Game Boy Color.
Locate the battery compartment on the back of the Game Boy Color.
Push down on the tab and hinge the cover downwards and outwards to remove the battery cover.
Remove the batteries from the battery compartment.
Using a Y1 screwdriver, remove the six screws on the back of the device as pictured. The bottom two screws are located inside of the battery compartment.
Gently lift and separate the back housing from the rest of the device. Now you've got the back housing out!