MV1B Stereo Mod info

[denial]

Hi all! I was watching the stereo mod for neogeo mv1b. I was actually wondering the point C indicated in the guide what signal it carried and because it needs a connection. I can't find schematics around .
Tnx for help!

 

[Neodogg]

@Xian Xi

 

[Neo Alec]

I believe there's a volume pot on the right side of the MV1B board, and that's what point C connects to. I think this mod is for line level audio, so maybe it's just tapping some audio ground from there or something.

Alternatively, there's this PCB:

OSH Park ~

oshpark.com