Courtesy Dora Shirk.
A little mishap occurred one Saturday night in October 1967. The caboose got shoved off the end of the caboose track and fell into the Thurston St. underpass that ran between the Railway Express building and the freight house/yard office in Wenatchee. This building was immediately to the left out of the photo. The caboose was repaired and had many more years of service before being donated to the city of Scottsbluff, NE and is currently used as a tourist information office.
Ben Thompson tracked it down and here is what it looks like in March 2020: