
It was signed by "Ulbrich"
I imagine this was done when the truck was reconditioned in Berlin in 1955. It could have also been done when it was reconditioned at Karlsfeld Ordnance Depot in Munich, although I believe only the engine was replaced at Karlsfeld.
The signature was under the dataplate to the uper right of the the glovebox (which I know is supposed to be on the firewall)

--Nick