As to reasoning for the 6 and 8 configuration, I was going to put the on board charger in the tray with the 6 batteries so I was trying to maximize that space to give some room.
But I have decided to put it between the seat backs, just incase the cart ever gets in deeper water than intended, I have gone thru water that came up on the brake pedal. I do not intend to submerse it but sometimes it winds up too late to change your mind.
So now I'm either going to put a 48-12v reducer there or an atv battery as I would like the possibility of using the winch, I just detest having to be concerned with another battery and charging.