Yes, it's I'm a dope time . . .

Got two a two battery set up in my '84 Westy.

Is there an easy way to determine if they are separate power systems,
one for the engine, and one for the living space, or wired in-line or
in parallel? And here's the really stupid one: In the case of having
to jump start the vehicle, which one do I attach the jumper cables to,
the battery behind the driver's seat, or the one behind the passenger
seat -- which of course has easier access?

TIA

Thomas