Built using plates 12 and 17 from the Seattle City Archives, this map was turned into a Windows Live Local mashup using MS Research's Mapcruncher.

There is an obvious correspondence between development and location of the line. Interestingly, growth seems to have been more likely to occur between stations along the line than along streets perpendicular to the line.

Here it is: The 1923 Use Map for Riverside and Highland Park.

If you like this, you'll love my modest-quality, but one-of-a-kind mashup of the 1911 surveyor's map.