373 2nd house battery location

[Newport Bob]

HELP!
Ready to upgrade to a 2nd house 4d battery and a larger alt. Can't find a place to install the 2nd battery. Bene manual shows a 2nd in the elec schematic, with inverter option, but a call to them = no known installation place.
MAIN SAIL - any limit on the cable length difference from the alt to the two house batteries on the same switch?

 

[Davefromoregon]

My 343 has three house batteries under the aft berth. No sure how standard that is.

 

[Newport Bob]

Dave,
Thanks for the reply. The 373 has the fuel tank under the berth. The one house bat and hot water tank are also there, aft of the engine. No room to add another.

 

[Stefan Gashus]

I have 2 additional 4DD batteries in the starboard locker of my 373. Requires some balancing out of a slight list to starboard but need the extra battery power for sure.