I have 3 house batteries (and 1 starting battery) on my, new to me, boat. Two are physically located together while the third is about 15 feet away. I spent the better part of a day mapping all the connections to understand what the voltage and current readings are telling me. The attached drawing (apologize for the simplicity) is my rendering of the system (only shows positive connections). I want to add/install a BMV-712 to monitor voltage and current of just the 3 house batteries but I'm drawing a blank on how to do it. There must be an easy way but I'm stumped. Any advice? Also, if you have any other advice on this setup, I'm open to it. TIA.