Wrecker equipment on Civil trucks

[Rolf S. Ask]

I am in need of photos of Holmes or Gar Wood equipment mounted on civilian trucks... Anyone who can help?

And another question, What is the wights of say, 20 inch wheels?
I mean the differences between Run Flat and Pneumatic tyres.
How much rubber did they save using five wheels instead of four?

And why is it mounted a spare wheel on the very early wrecker on the picture?

Rolf