Article is being updated
Preparing your Gameboy shell is relatively easy and requires few tools. I would recommend having at hand...
Remove the cartridge guard
Remove the two posts shown in the photo
Remove the battery springs
Remove these posts from around the LCD including the raised plastic surrounding the POWER led
Remove the post next to the buttons
Place the Button Bracket / Drill Guide into your shell
Using a small drill bit, drill a pilot hole
Using a stepped drill-bit enlarge the hole to 11mm. Go slow for a better and more accurate finish
Use a sharp knife to remove any excess plastic and to smooth / soften the edge
I sometimes use ScotchBrite to further "sand" the edges to soften them