Robin,
It was not just down to me, a friend in Paris, Serge, told me about it and said he thought it was a Morris Commercial ambulance. It was surrounded by material in the building and he could not see the front end. This raised my interest, but a few photos from him gave me enough clues that it was an Austin. Knowing Radek was desperate to find a K2, I put him in touch with Serge. Actually last week Serge sent me a link to a short video of Radek driving it around a field, so Katie lives and breathes.
regards, Richard