I found this 1943 topo map that shows a siding at Four Lakes, WA along the NP CW branch. In modern terms the siding extended from the I-90 overpasses to half way to Craig Rd. The siding was gone from the 1954 maps. I had not previously realized there was a siding there. A few years ago the switch into the Highline facility was installed into the mainline about the mid-point of the old siding.