More to come as I document the process.
Looks like the battery had corroded away the traces for Pin 19 and 22 for me. There is still a fault somewhere as there are very slight traces of lines still in the image. I am hoping it is only 1 more pin.
Neo-ZMC2 pin-out
https://wiki.neogeodev.org/index.php?title=NEO-ZMC2
Neo-257 Pin-out
https://wiki.neogeodev.org/index.php?title=NEO-257
References:
https://www.youtube.com/watch?v=GbiYcLPQY_M
https://www.arcade-projects.com/threads/help-needed-mv2f-vertical-lines-no-sound-2-slot.15043/
https://www.arcade-projects.com/threads/help-with-non-booting-neo-mvh-mv4-and-2-slot-with-lines-in-sprites.9714/
