This has nothing to do with the German Panzerzüge. The Wehrmacht was owner of the Panzerzüge, but here we talk about the Reichsbahn.
So they came up with two types of armed trains. Both were eaysy to adapt and were based on existing material.
Geschützwagen type I with 2cm Flak |
Geschützwagen I with 2 cm Falk |
Geschützwagen type II with two concrete towers |
Geschützwagen type II with two concrete towers |
side view of the type II, on some pictures you can see them with Drillings instead of the 2 cm Flak |