I bought a battery tray to fit the size battery I was to install with the tie downs. Used liquid nails and stainless self tapping screws and the rest is history. Since I owned a 2008 180 the battery fit next to and to the rear of the factory battery. For pictures of this install look for "Challenger upgrade pictures".......posted 2-18-15. I also added a Perko two battery switch and of course cables. Been in rough seas and the batteries have stayed in place.