Sorry Quiller et al, but according to at least four independant book sources this car is NOT a Hong Qi prototype!
It is a 1968 Shanghai SH-761, of which a handful were built from the late 1960s until the early 1980s. My scanner is currently kaput, but once it's working again I will scan the same image that you first used, with supporting text all stating that it is a Shanghia SH-761 from two French publications, plus one German and one Italian. Sorry!!