Check your Georgano for "GM" and you will find nothing about the Detroit car makers or their wide range of products. In stead you will find a few odd lines of information about the short lived (1924-1928) French make Gendron et Michelot. The sad surviving 1927 model CG6 depicted here - check this similar one in better days - found an owner who took up the recommissioning. Hardly any info regarding the marque is available online excpet this nice period show photo and here where we found that G.M. participated in the 24 hours of Le Mans of 1925. This was however a type GC2. Sender of the photo 'Polo' is looking for engine parts, we can only wish him luck and suggest to try a search advert. With a product of the US based GM he probably would have less of a problem locating stuff.