The Germans used the chassis of the A7V tank for a simple carry cart vehicle to supply the front lines. The French used converted St. Chamond tanks while the British used converted Mark tanks. Why didn't the Allied forces resort to using their own tank chassis to make carry carts, which should have been simpler to manufacture and operate?
Imho, the British rhomboids didn't have a chassis. I'm sure someone will explain it better, but the rhomboids couldn't be modified in that way. The use of the Gun Carrier was a bit of improvisation. But the Allies clearly came to recognise the need for an all-terrain supply vehicle, and the answer was the Newton Cargo Carrier. An order for 20,000 shows they took it very seriously.
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