Not sure if anyone saw it but there seemed to be the original chassis plate for AEX 164 on e-bay. The auction / sale has now been withdrawn. The "buy it now" price was approx. 1,400 GBP. The advert / auction said:-
Offered is an original brass manufacturer's identification plate for A.C. Cars Ltd. This item was on a dismantled 1957 Ace roadster. Engine number CL2288W and Chassis number AEX 164. The plate is 8 inches wide and 3 1/2 inches tall. The condition is excellent with no pitting - all black letters are clean and intact. The stampings for the engine and chassis numbers are clean and deeply stamped. Both numbers were factory hand stamped. This plate is appropriate for A. C. models that did not have Bristol components and accoutrements.