Where was my old boat customized?

[Larryrsf]

Yeah, I see the distribution panel behind the dash. Pretty corroded, but probably OK. I may pull it down and replace it. Several of the circuits are fused.

I added another battery and will connect the other stuff to that, bilge pump, lights, GPS, cigarette lighter powered stuff. Maybe a radio.

What is the best way to interconnect the two batteries? Obviously if they are always in parallel, they charge and discharge together. I would think a switch would be best so that the alternator would charge the auxiliary battery only when it needs it and only the primary would supply the starter.

Larry