After Mr (later Sir) David Brown bought Aston Martin and Lagonda, he asked Maurice Jones, who was the chief experimental engine engineer for DB's tractor division, to evaluate the power units produced by both companies. These blueprints, which include drawings for the AM 4-cylinder 2-litre (dated 1945 with Claude Hill's name on them). Lagonda LB6 and pre-war Lagonda V12, were used as part of the evaluation process. They were kept in Maurice's office at DB's Scarr Bottom engineering department (now a Morrisons supermarket) in Meltham, and I later managed to purchase them from his family. Maurice evidently deemed the LB6 to be the most suitable engine, and a new set of drawings for this unit was prepared by the drawing office of David Brown Tractors Ltd for production at Farsley. They all tell an interesting story!