I recently set out to repair a nonworking Chiller game for the NES, and made a few things in the process. I've attached here board scans of the bare PCB as well as Kicad files for the schematic and PCB. I did take the liberty to add an AVRCICZZ to the board, but everything else is an original part. Hopefully this will help anyone else looking to understand or fix these boards.
The Kicad files: The front board scan: