Hi there!
I got a tip about this on-going topic at this forum from a fellow member at the Swedish modelbuilders forum "Modelbygge iFokus".
Since My latest project actually was the Jo-Han kit of the 1934 Mercedes Benz 500K "Roadster Limousine" i thought I maybe could help you with a picture of what i guess probably is Rudolph Carracciolas MB 500, photographed in the 1980:s, probably in the US. I found the picture (attached) just by coincidence while looking in one of my almost forgotten books; "Classic Cars", by Richard Nichols, Bison Books UK 1984. The coachwork, the body-color, the white-wall tyres, and the overall general appearance of the car at the photo is similar to the on on the "box-art" of Jo-Han's kit. So far, the picture in "Classic Cars" is the only one looking like the box-art car that, in the text on the outside of the box, is said to have been specially ordered for Rudolph Carracciola, and later sold to a collector in California. The three other attached pic's shows my own, dark blue version of this extremely beautyful car.