I had this large empty space behind the motor and since it is ventilated while the motor is running/charging it made the perfect place for the new batteries. As well, the gr 27 batteries are vented into the engine space.
The base for holding the battery box...........
Aft mountings for holding the base. Attached to the strut thru bolts.
I made a pair of 3/4" studs that screwed onto the 3/8" thru bolts, and added washers/nuts to hold it down.
Also added a front and side tabs to help support the base.
Reinforced the corners with wood and epoxy filler, then glassed over with a couple layers and faired in for the paint work.
Added a couple straps with release levers to hold the battery box in place.
I also added a 2000 watt inverter, which required using 1/0 cable, but I went to the 2/0 through out the system except the starter cable. Which I left as a #2 cable.
I couldn't find a terminal crimper locally that was large enough so I just modified a hydraulic one that I had to do the job.
Finish product.................................. Then added heat shrink insulation.
I went with two 6V deep cell batteries in series for the house side of the switch, only because they were so heavy I couldn't get a large 12V into the space w/o special help. I prefer being independent, not relying on other people to help.
These are the gp 27's with all new cables with breaker switches.
Also added a Yandina 160 combiner to charge both banks while running. In the back is the breaker for the house (2-6V) batteries.
The starter cable is hooked to the common of the selector switch, which goes threw either the 27's breaker #1 or house breaker #2, or both.
I also have a gp 27 battery up forward for the windlass and wash-down pump, which is attached to the common of the selector switch. It is controlled by a Yandina 50 combiner at the battery. See the windlass page.