I recently built brackets to hold batteries in the former Gas Tank cavity. With the batteries temporarily mounted, I also cut and crimped all the 2/0 AWG wire for all the front packs. In total, the gas tank cavity holds 6 packs = 24 cells.
Picture above is the 16 cell main gas tank cavity pack resting in its aluminum frame.
Picture above is 8 cells grouped in 2 packs of 4 cells. One mounted vertically above the steering linkages, one horizontal directly above the future location of the 16 cell pack.
This photo is the same cavity, just panning the camera to the left to show the 2/0 AWG orange wires, hydraulic steering pump, hydraulic lines (clear tube with green fluid), and steering column stuff in the background. Once the 16 cell pack gets inserted, these views will be hidden.