This picture - Bundesarchiv_Bild_101I-121-0010-20 – was taken on the 1st of September 1939 near Bagnitz (now Bagienica 53.445 N, 17.795 E). It shows German 3rd Panzer Division.
According to book ‘Panzer Divisions Blitzkrieg Years 1939-40’ – ‘tactical symbol on the left mudguard denotes a motorised infantry platoon’.
Because 3PzD Schützenkompanie was organised according to KStN 1114 from 1-Oct-37 which apparently has not survived, that picture is really worth analysing.
Infantryman on the back seat of the staff car looks like Entfernungsmessman to me. You would think he would be rather in s.MG Halb-Zug of Schützenkompanie, not in the Schützenzug.
But according to Dr. Leo Niehorster, there was no staff car in s.MG Halb-Zug.
Also what do you think a soldier next to Entfernungsmessman is holding? Could he be a Krankenträger?
Anyway lots of things to look at. Might help to restore details of this early war KStN...http://commons.wikimedia.org/wiki/File:Bundesarchiv_Bild_101I-121-0010-20,_Polen,_Kolonne_motorisierter_deutscher_Truppen.jpg