Sorry guys I think I am still confused. So please bear with me.

My buddy wants to play Ikari Warriors the most, so he is building his panel around that. So today we bought two rotary opticals, an optipac, an ipac2, a spinner, and trackball.
The optipac says it can handle the spinner, trackball, and two rotaries. However this connects to the PC via ONE USB correct? It appears to have an output for a player 2 serial as well. But do you know if these function at the same time? From the ultimarc site it would seem I would need to have the optipac connected via two serial cables.
Also with normal mame (v102) (not the multiple mouse enhanced beta version or analog mame), can he get a two player Ikari Warrior game going? If so, what connections or configuration is required? He has XP.
The optipac he is getting is USB version. So we might need to get an extra serial cable right? Or perhaps even two serial cables and just forgo the USB altogether.
The spinner is USB and will be connected directly to the PC. So the only things going through the optipac will be the trackball and the two rotaries.