How to build a "jamma+" connector for Midway (MK)

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For MK2 u can use the same adapter.
For Pinouts on MK2 use the following:
Locate pinout connector "P5" aka "Player 3" and connect to Pins
7-13 (7-9=Player 1, 11-13=Player2, 10=not used). Volume Control is on P16, Pin 2