On/off/on rocker switch

I am wanting to install an On/Off/On Rocker Switch, by my understanding this is also known as a Center Off Switch. This Switch will control a shop vac. The Switch will be set up as Manual On/Off/PC Control. I am hoping someone can answer a few questions for me for this installation. I know that the center lug will go to the Input 3+ on a SSR-25DA Solid State Relay. The PC Control will come from the Gecko G540 PIN 5. The Manual On will come from one of the power supplies. Should this connection be made using a 12v or 5v Power supply? I assume that the 48v PSU would not be used bc the SSR is only rated from 3-32VDC. My enclosure will have both 5v and 12v PSUs.

I would also like to use an illuminated switch, I assume this might also dictate what switch that should be chosen.

Can somebody please enlighten me and point me in the right direction

Thanks