You'd need the security pic, bios, probably a sound rom, Carnevil compact flash or HD, and the gun io board (oh and the guns...). But the Atari/Midway Seattle base is the same.
You'd need the security pic, bios, probably a sound rom, Carnevil compact flash or HD, and the gun io board (oh and the guns...). But the Atari/Midway Seattle base is the same.