377V Dual 12v Battery Setup

[olmnsml]

Question: Has anyone done a dual 12v battery setup on a Vengeance 377V yet? I have a 2017, with an existing battery compartment on the passenger's side. The negative lead connects to the frame right where the generator compartment is. And I am assuming that the positive goes over to the battery cutoff switch on the drivers side compartment, which is where a second battery holder is located. Wondering what would be the best way to accomplish a dual setup, and if I need to run another Negative lead to the other side to connect the batteries.

[SeaDog]

On the three dual batterie setups I have (TT,ranch truck,boat) all are wired with the batteries connected.