The rear reverse seat was not placed there for an MG, however in the latter years of the war, it may have been utilised as an ant-aircraft spotting seat, there again just because I have not seen any photos of an MG mounted on the rear, does not mean it did not happen. All the photos I have seen, show MG34s deployed on AA tripods around the unit, to add to this, memoirs talk of soldier abandoning the vehicles for the nearest ditch with their rifle.
It was originally intended as Adrian quite rightly says, for making sure the towed unit was nott lost, or tipped over whist in transit.
Here's a nice photo of it from Vinces Gallery
As you can see no post was fitted for an MG as standard
Paul
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