I found a picture of the real truck on the Internet. It is a 45 ton Foden quarry truck called FRD/45 but I can find no more information, it was true though that the steering linkage ran outside the bodywork, just like in these pictures. I'm guessing it was a 1950s machine as Matchbox released it in 1961. The next King-Size K-5 was the Racing Car Transporter released in 1967 so I guess this one carried on until then.
There are some rare and valuable versions too. Orange Yellow cab & tipper with red wheels - probably a late release with plastic wheels - is the best price. Next best is the orange-yellow cab with the light yellow tipper
