Mike never raced a 500, as far as we can tell but, in the summer of 1952, various cars and drivers tested the soon to be reopened Crystal Palace circuit, as part of the preparations and to demonstrate to the Council that the circuit was viable.
Mike was there to drive his Cooper Bristol but also tried John Cooper's Mk VI for size and is clearly enjoying it.
It seems to have inspired him as the following appeared in Iota in September '52. We have no evidence that he took this further as, by 1953 he was already driving for Ferrari.
Having firmly established his reputation in the Cooper Bristol. Mike went on to win Le Mans in 1955, paired with Ivor Bueb and become Britain's first World Champion in 1958, infamously beating Stirling Moss. Mike's team mate at Ferrari was Peter Collins who very much cut his teeth in 500s. Peter's death at the Nürburgring, along with the previous loss of Luigi Musso had a great impact on Mike who retired at the end of the season. Sadly he had all too short a time to enjoy life as a World Champion.