Lastly, insert the microSD card if you haven't already. You should have already burnt the PiGRRL image to the SD card. If not, go ahead and do that now!
Hazzah! The PiGRRL 2 game console is finally finished and ready to play! Turn it on and RetroPie / Emulationstation should automatically boot. The buttons are premapped to the expected controls. Reference the Software page for uploading ROMs and remapping controls.
If you built PiGRRL 2, we'd love to see it and share it with the community! Post a make on the thingiverse project page, share it on Instagram or twitter with hashtag #PiGRRL2.