In the Dutch Citroën magazine CitroExpert (#48 from 2004) is an article about this Wanliss car. Not only the roof and the windscreen were raised, also the drivers seat and the steering column were 1 inch higher, and the fabric roof was replaced by a solid one (even though it still looks like fabric). These conversions were made by Citroën Slough themselves, not by an independent coachbuilder.
In pre-war times Major E.O. Wanliss from Lytham Saint Annes in Lancashire was in Hong-Kong, where he got infected with tuberculosis in his spine. After serveral operations which didn't really help he had to wear a corset and still his back was very weak and he couldn't bend his back or his neck. The 2CV appeared to be the only car with a suspension soft enough for his weak back, but he just needed a bit extra space.
He made several holiday trips with this car, to France and to Switzerland. During one of these trips he had the original 375 cc engine replaced by a 425 cc version, which is still in it, nowadays.
Chassis number is 8530102, engine number looks like OKD6707 (Echange Usine).
Later, after his retirement, Major Wanliss bought a Citroën DS, and in 1991 the remains of the 2CV were bought by Mr Les Rawstone from Kirkham, who restaured the car.