Although I don’t have a cabinet I would think the list would be:

directional buttons
Minimum of three action buttons (6 if playing fighting games)
Start
Insert coin
Exit

I think exiting would bring up the emulationstation menu. You definitely need a start and coin button. Select game isn’t needed as its emulationstation you can just map it to one of the action buttons.

On my xbox controller I have all those mapped anyway.