Japanese MVS board questions

I'm pretty unfamiliar with the MVS system, and I recently acquired a Japanese board with a MAs supergun.

1. How do you wire in the 4th button to work with the Neo games?

2. Any way to change the language settings?

3. The MVS board i have has controller ports hardwired, so I've been using my AEs controllers until I can figure out the proper arcade joysticks. A statement really, not a question.

4. leaving the MVS board exposed...Problems other than dust and such?

Thanks in advanced, guys.

1) connect the wire from pin 25 on the jamma harness (right after button C) to the right pin on the connector. <a href="http://www.gamesx.com" target="_blank">www.gamesx.com</a> for the pinout.

2) only with a bios replacement, i.e. unibios.

4) nope.

Thanks much