Mapping FBA controllers to player 3

[Sk8ersublime]

So I am having a different issue now with FBA that I cant figure out.

I have 19XX running in FBA in my 4-player cabinet. 19XX only runs well with FBA, otherwise its extremely slow. So on my 4-player cabinet, I like 2 player games to use the middle 2 controllers, in this case Player 2 (connected to Jamma) and Player 3 (connected to RPi 4-player adapter board).

At first I couldn't figure out how to map the controls of player 1 to player 2, but then i realized i had to change the input device to GPIO controller 2 under Bind Player 1.

But I cannot figure out how to get Player 2 mapped to my Player 3 controls, it doesn't recognize any key presses from players 3 and 4 on my cabinet in FBA. I tried all of the Input options.

Any suggestions?