Construction is coming nicely along with the OCS (Overhead Contact System) in place from Tukwila International Blvd Station to I-5/SR 599 and Mlk Way/Boeing Access Rd to Raymond Street. The bridge linking Tukwila Station over SR 518 to the Airport is complete and ribbon rail is along side of the new Airport Expressway that is currently being welded.
First Up, Mt. Baker Station
I’ll have to take some time out this weekend and explore the Airport Segment more in-depth. Not any places I would recommend stopping at near the Airport where you can get photos of the construction though it may be a thought to take the bus to the terminal and walk up to the top of the parking garage and shoot down towards the alignment. I’m sure you can get a good vantage point of the Expressway and might be able to see the Tukwila Station as well.