On my 2004 Cougar, I cut a piece of 3/4″ plywood to fit across the sump from battery tray to battery tray. Its nothing fancy and it is easily removed. I then screwed the battery charger to the plywood. Works for me.Jim EbarbMany, LA (Toledo Bend Lake)2004 Cougar/ 225 OptimaxHumminbird Helix 12 Chirp SI on BalzOut Mount at bowLowrance HDS 7 at bowHumminbird Helix 12 Mega SI on Ram Mount at ConsoleLowrance HDS 8 in dash at console