The photo is from Wilmot Hills in 1954 with Bud Seaverns at the wheel. For some time I thought this may have been ST*403*BC but John de Boer has supporting documentation of this being a different chassis number.
My initial reasoning:
ST*403*BC was bought by Herbert Whiting of the mid-west on 12/31/1953 without a grille. ST*403*BC was one of a few cars delivered without a Bertone badge on the side and there is no Bertone side badge visible in this photo. Bud raced this Siata 300BC other times in 1954 including a races with Larry Whiting driving a different car. I thought there may have been a connection since Herbert and Larry share a last name. I wanted to believe that this was part of some “lost” history of ST*403*BC but it now appears to be a coincidence. This is just another example of how confirmation bias and the Internet can make one jump to conclusions that are wrong.
Photo Courtesy Julian Silverberg.