I just acquiered a Mortal Kombat II arcade game and everything works but the sound. the ribbon connector from the cpu to the sound board is disconnected but i don't see a place to ribbon on what i think is the sound board. Please help.
There is a picture showing where the boards mount on page 1-5.
As for the wiring diagram, I'm not sure why that isn't answering your question... That has to be one of the clearest diagrams I have ever seen..
It actually spells out that the ribbon cable connects from P4 on the Sound Board to P12 on the CPU board. You also need another cable to go from P1 on the Sound Board to P3 on the CPU board. Normally they don't put all that text confirming everything...
The sound board is separate, on some of the early mk2 pcb's they had a daughter board that plugs on top of the main board and some people get that confused with the sound board. The sound board ribbon cable plugs to the main board by plugging the ribbon cable to the 2 rows of header pins. Sound like you may be missing the sound board and thinking the daughter board is it.