I am getting a 17MKE and order a Battle Born Lithium battery for the trailer. I am getting the solar package. I would like to place the Lithium battery in a lock box. I already checked "https://www.rvlockbox.com" and their boxes are not waterproof. Had any one else replaced the battery box on the trailer with an after market box? Or is there a way to lock the box that comes with the trailer?