Tom - Many thanks for the info. AEX 198 was originally an AC-engined Ace that left the factory in August 1956. It was white in colour with green leather and carpets. It was an East Coast car, imported by AC Imports, Arlington, Va. I have no history of the car as it only first 'surfaced' (as far as the Ace Register is concerned) in 2006 when it was advertised on e bay USA by a dealer in Arizona. The pictures showed the car now red in colour with the body modified in the 427 style and Halibrand wheels.
Thank you again for the update, and I'll make a note to the effect that the car is back up for sale again this year. Maybe someone else knows something of its earlier history?
Tim