Demag TC 500 truck crane in scale 1/24

[Zabco]

How old is that trailer design? Got to looking around the internet to see if I could find some info on it and there is almost nothing. Found one picture on the Scheuerle company web site on a history timeline that says it was introduced in 1949!

Found a guy on a german modeling forum who built one in 1/16 scale and it appears his has crossed chains running underneath the trailer to connect the front and rear bogies. Is that how yours will work?

Looking forward to seeing more photos of this build.