2003 203 dual console. I'm switching from a 24v to a 36v trolling motor. I really don't want to totally redo all of my batteries and power pole plumbing in the back, not do I want to add more weight back there. I was thinking about putting the third battery in the rear of the port rod locker, butted up against the passenger console. Will this work ok? Any suggestions on how to secure it? Thanks!