Early chevrolet in desert war

[motto]

Here's a chance to show my ignorance. As I understand it a number of Chev trucks were obtained by the military from a GM dealer or dealers in the Middle East and modified for desert use. This would inevitably lead to a variety of trucks being pressed into service. Given the commercial predisposition to mix and match along with the urgency of the situation also with the presence of military contract vehicles i.e. Canadian sourced or Indian army pattern the possibilities are endless.
The two trucks in the first picture appear to be modified commercial trucks known in Australia as Lend/Lease Chevs or '42 Chevs though I think that in other parts of the world this sheet metal appeared in '41. In Australia most of these trucks had ten 9/16' studs holding the rear wheels on and five on the front. All wheels (20 inch) had the ten holes but on the front there was a plate that went on under the nuts that only had the five holes so the wheels appear to be different.
With the possible presence of Maple Leaf trucks or their components and the obvious use of 16" or 18" single wheels with a different stud pattern again the situation becomes somewhat confusing.

Help needed!

David