Comment: It is not uncommon, depending on what facts are known on a Spohn Custom, to either refer to the car either by the year and make of the chassis or to call is a 19__ Spohn, referencing the year Spohn did the body work. Still, the attributes of the Jaguar in question and the background cars could easily indicate that a 1957 Jaguar chassis was the basis for Spohn's 1957 coachbuild.
For consideration: perhaps the Jaguar cat was connected to the hood/bonnet latching mechanism and turned 90o for release. Having been left that way may have been the cause for the photographer to take the photo.
Question: what year is your Citroen Traction 11B chassis of your Spohn coachbuild? Was in bodied when new or re-bodied in a later year? The frontal appearance is of some other '40s Spohn builds. How is the car titled? Do you know of other Spohn-Cits?