Steve
I think that it is extemely importantant that the parallel wiring between the two batteries be as equally matched as to length (and resistance) as possible.
i.e., the neg to neg and the pos to pos wires need to be exactally the same.
And... the Anderson quick connects work well... they match the wire gauge.
I agree that audio shops have the best wire, fuses, and connects
I added a
link where you can see the ones that I recommendI think that you should consider a pair of AGM's... hydrogen gas from batteries inside your camper is too risky. Sally is much too precious to risk.
sleepy