Something substantially different to say the least with a street grid being raised 10-30 feet:
http://surewhynotnow.blogspot.com/2018/05/seattle-underground-and-great-street.html
Found a hand drawn 1884 bird's eye map of Seattle before the 1889 fire. Mill Street (Yesler Way) can be seen on the far right with the massive hill that was in place before the city street grid was regraded:
http://www.historicmapworks.com/Map/US/54345/Seattle+1884+Bird+s+Eye+View+24x42/Seattle+1884+Bird%27s+Eye+View/Washington/