In my mind I currently have my back deck off the top of my rear seat to the transom fully enclosing my gas tank except for a 5x12" slot i cut out for venting in the back (i am not sure it is enough). I have heard gas fumes are heavier than air? The problem i have is that my battery will also be contained in this area and sparks may eventually fly from connecting the trolling motor or any number of things. I am not really sure this is going to be safe? I am wondering if anyone out there knows how so many of the boats on this site seem to have covered gas tanks? What are the steps i need to take to keep the fumes out and ensure it is going to be safe? Thanks for any input