GBZ Misc Hardware
From sudomod
GPIO PWM Audio for Raspberry Pi Zero
150 Ohm resistor, 270 Ohm resistor, 10nF capacitor, and a 33nF capacitor (another 10nF will work fine as well if that’s easier to find)
L/R Buttons
If you want to use tactile switches in the rear screwholes like the original GBZ, you'll need something similar to this: http://www.amazon.com/9-5mm-Momentary-Tactile-Button-Switch/dp/B008420WOA or this
Replacement case
A replacement case for the gameboy can be found here.
Audio Jack
In case you can not use the audio jack of the original GBZ board here is a replacement.
