You *could* use the JPAC for only video, but then you'd have to re-wire the joysticks and buttons on your control panel to go to the mini-PAC.
Why not just use the mini-PAC for ONLY the spinner and trackball and leave the joysticks and buttons going through the JAMMA harness and JPAC? Your joysticks and buttons should be already working through the JPAC.
That will save you a lot of unnecessary re-wiring. Why re-wire when you don't have to? Plus, if you keep the JAMMA harness joystick and button wiring intact, you have the option of running real JAMMA games in the cabinet in the future if you choose.
Are your trackball and spinner standard arcade-style optical devices (i.e. not USB)?
Then a better choice than the mini-PAC would probably be the Opti-PAC...
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