It is a good job you did not include the Y4 Duesenberg in a 1/43rd scale lot because that model is not 1/43rd despite what it says on the box etc. I had both the Yesteryear and Solido Duesenberg models and the yesteryear on no planet I know is 43rd scale!
For the purists out there, the inclusion of the Yesteryear Y-6 Rolls-Royce Fire Engine by Bob in the above 'Test Game' is simply because the stated scale on the model's box is 1/48. This is a default fact because the model uses the base from the Y-7 1912 Rolls Royce from the same range of models and the stated scale for that model is 1/48.
The real car the Y-6 Fire Engine is representing had a 150 inch wheelbase (3810mm), the model has a wheelbase of 68mm. 48 x 68 = 3264 but 3810 divided by 68 = 56 making the model c1/56 scale.
The models were often "adapted" to make them visually more attractive. The MG in the first picture is an example of this. If it were accurately modelled, it would be narrower than the model we have. If I remember correctly, the Spot On MG was proportionally more correct than the YY example.
Well it turned out to be a red herring if Ghosty's guess at that stage was anything to go by! The (cryptic) clue was a reference to "scales" but went over the head of the participants it would seem.
nice one Bob. 
