The batteries have been loaded into the main battery box. Here's how it went.
I previously showed connecting the exhaust vent and fan to the rear of the box and to the back of the trunk. On the front side of the box I had previously made a cutout for the battery cables to run through. Using a hodge-podge of electrical and plumbing fixtures and adapters, I cobbled together something which connects the conduit which I had previously installed in the hump and the front of the battery box. Here's a picture of the hodge-podge in place.