We need a pic of the lay out of the rig. I have 4 large batts on board, one is under my console not due to room but more because of weight in the rear of the boat. Heck my 4 bank charger is dang near big as a batt but only weighs 30 instead of 90 pounds so it get to ride in the back. I built a deck extension in my rig and know a lot of others that have done this and used it for batt storage.