Need battery boxes

I have a century plastics battery box for four 6V batteries. They have many sizes. Just Google Century Plastics battery boxes. You will have to cut your vant holes and drains. I also added a foam rubber seal around the lid and taped around the cables to seal the box up. I used ratchet straps to hold the lid down against the seals. Or you could just duct tape the whole thing up (like I did for ten years). They are very basic as they come but you don't have to build the whole thing.