We always thought it was the area South of Cermak, but evidently it extends North all the way up to the 1400 block of South Michigan. How do we know? Well the city just put some signs up designating this area "Motor Row" as well:
For those who can't read what the sign says, here you go:
Considered to be the largest and most intact early "automobile row" in the United States, the buildings of Motor Row illustrate the early 20th-century evolution of the auto showroom and related service buildings. Larger windows displayed the shinning machines in tall showrooms, while service and storage facilities were located on upper floors. In its heyday in the 1920s, as many as 116 different makers of automobiles were being sold on Motor Row. Parts suppliers, accessory manufacturers, and repair shops clustered nearby.
History is interesting.