Any idea what the extra batteries are for on the LHS?
These Okas have a dual battery setup as standard (one each side just behind the front wheel) but the large battery bank is installed in lieu of a second fuel tank.
Don't look like Comms vehicles to me.
There were some Okas with a bus/van type body setup for Comms with the RAAF. They had a hydraulic pump on the front of the crankshaft driving a generator that charged a battery bank just Li,e the Okas in the photo. These Okas have winches and I don't think there would be room in there for a pump as well. The vans didn't have winches as far as I know.
Pete