As we have spoken, I have a start, genset battery and a pair of T105 6V GC batteries for the house. Not running a lot, but would like a bit more capacity. We run genset a couple times a day for 2 hours. House bank usually around 80% in the AM and 85% end of day. Genset brings it back to 90-95%. I am looking into solar panels also.

Anyway, not too much room on my ‘94 390CPMY. I was thinking of placing the 2 additional 6V GC batteries in an appropriate battery box and placing them forward in the galley area under the floor hatch. I could make a bracket from pro to starboard and put a shelf for the box to rest. Then run the heaviest cables I can get to join them to the other set of house bank that is between the engine. Should I be concerned about the off gassing? Seems like we have some ventilation down there. Here is where I am planning on placing them. OR I could relocate the shower pump 90 degrees to the left and place the batteries to the right of it. I think it close enough to the center line to to make much, if any lean.

Ignore the water in the bilge, as I put bilge cleaner in there and turned on the hose. I will get it up on plane on my return trip to have the center bilge pump remove it.