But what if I don't want to use the original JAMMA controls?
Why not? What *do* you want to use?
I want to use a ball top joystick and different buttons. Also, I want more buttons per player.
I think you are misunderstanding ... by all means, disconnect the JAMMA harness from the existing controls and put new controls in. Then connect the ends of the JAMMA harness to the new controls.
EDIT: When disconnecting the wires, I recommend labelling where they came from for easy identification and reconnection.See how you only had to connect some wires for those controls that are JAMMA standard ?
What about extra buttons, you ask ?
Well, now you run the extra wires from the extra buttons to the extra spots on the JPac. But you are only wiring a few buttons per player (since the sticks, coins,P1,P2 and first three player buttons are already wired in the harness), so is a big timesaver.
Oh, almost forgot ... you didn't have to do any wiring at all for that arcade monitor. That's nice, particularly if you are not so sure of your cable-hacking or open-frame monitor abilities.
Did I mention that you are now done and ready to go ?
I don't think I know anyody who keeps the original controls when MAME(tm)ing a JAMMA cabinet ... I sure don't. In fact I will rewire a stripped cabinet JAMMA and drop in a J-Pac because I prefer it to wiring an I-Pac2.
Cheers