PzKpfw IV at the front : UPDATE No3 - factory production guide (G)

The heart of this book is the exploration of factory differences during the production of Ausf Gs. I have been able to identify a number of features that can enable the differentiation between vehicles of a similar time period. That is, if you can see certain elements you can confidently ascertain whether the vehicle was build at the Krupp, Vomag or Nibelungen factory. These range from new observations on small details to realigning features that were previously thought to be date specific alterations to factory specific styles.
The key to this research was an investigation into new and existing images of vehicles with their Fgst Nr (chassis number) visible, I have managed to gather over 40 such example, 12 of which are documented photographically in the book. These are relating to a chart built around info found about contracts given to the specific factories. Within the book there is total of 139 photos covering the period from early 1942 through to mid 1943, as usual the majority of them are previously unpublished. I have split the update into the following four periods: early F2(G) where the differences are harder to spot mid G where they become quite distinct late G where other distinguishing feature are added (including diagram showing schurzen variations) and very early H.
There are 9 diagrams, three tables and multiple thumbnails introducing specific details in each of the chapters. The book concludes with three models of mid production Gs illustrated with 11 photos and showing how to accurately produce one from each factory.