550-0054 was completed on 14th July 1955 in silver with blue darts and fitted with engine #P90048. The spyder was shipped to the US, for an order placed by west coast driver Bob Donner who started racing it in May 1956 at Bakersfield where he finished 8th.
After a number of races at tracks like Pomona and Eagle Mountain, he was able to master the spyder with many podium finishes. His last race was in December 1957 in Phoenix.