J.A.G.?
YYEESSSS!!! At last. Well solved - nobody asked if the engine was a Ford.
It's from an advert in the 1950s which claimed it was a 1947 car, but according to the Georgano encyclopedia J.A.G. began making cars in 1950. Possibly the engine was from a 1947 car and that resulted in this car being registered for that year.
Georgano also reckons they made about 50 cars altogether, which seems a high figure to me. Some were 1172 s/v powered but this is a V8, maybe from a British-built Pilot.