Old Washington State highway maps

My Grandfather served for 16 years in the legislature from Yakima and was the single most person that got Chinook Pass built. It was supposed to go over Naches Pass and be an all weather highway,but Grandpa loved Yakima Park,now Sunrise, and Chinook Pass was a closer for the family. He was also worked on the survey of the park boundary in the very early 1900's. My uncle liked to tell the story of them riding on a flat bed truck to the dedication and one of the dual wheels stuck out over the edge aeveral times.
Does anyone remember the highway to Pullman in the 50's,when it went through Othello,Washtucna,Hooper and ran along the river towards Dusty. It had 90 dgree corners at some property lines where the farmers didn't want the road cutting across their land..