Capacity of Truck in Photograph?

[Lionelgee]

Hello All,

What would the carrying capacity be of the single rear axle Chevrolet shown in this Australian War Memorial photograph?

Does the vehicle have a disruptive pattern or is it just different shading in the photograph? It seems a different shade between just above the middle of the mudguard to just before the "S5" painted on the door.

Photo accessed 14th October 2018 from https://www.awm.gov.au/collection/P03369.002

Also, can anyone identify the trailer/caravan or rear truck body seen in the background just beyond the bloke's right shoulder who are standing in the tray? The background vehicle in question has the load on its roof and a couple of what look like to be windows in the side.

Kind regards
Lionel