These were produced by Janet Hill in around 1990 (maybe earlier).
I purchased the remainder (around 120 sets) from Ken Hill sometime between 2006 & 2008 and there was one in each room of the hotels I was using for the Le Mans Classic. There was a beer for the first person in each hotel to produce a pictures of the completed puzzle.
If you have not manages it by the time of the next BHM Breakfast meeting I will let you in to the secret!
One amusing thing Ken told me was that one Christmas Day he had a telephone call from someone in New Zealand, who had received one as a present and was convinced that it was not possible!
Quentin
