Jon,
Try Granite State, his research may have touched upon armoured cars elsewhere and pre-1939.
I cannot recall any such German memoirs, although there are some British. Perhaps looking at the divisional history of the German 90th Light Division and other, smaller formations in North Africa would suggest lines of research. German armoured cars appeared in the blitzkreig years in Europe, but other arms were in the limelight.
Might be worth asking the UK Tank Museum / UK National Army Museum, as there maybe post-WW2 documents?
davidbfpo
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