I am not sure about the artist on this one. It most likely was by one of the California guys Jim Hastings was using during this time. The signs say the car is in the eastern part of the country but that does not mean the illustrator was not on the west coast.
Still, the artists Hastings was using from there usually signed their work and this is not signed so it could have been done by a Detroit illustrator. Hastings was bringing along some of the local talent and getting good results.