Regarding the Boeing Fuselage questions; here is what I have learned from local observations:
1) The fuselages do not travel under guard; the caboose is only assigned to the local that brings them from Balmer Yard in Seattle.(BNSF offers cabooses to various locals in the Seattle - Tacoma area, for use in backing moves & such. Conductor's option.) I have seen the fuselages enroute many times, as far East as Essex, MT.; sometimes as a special movement, often on the headend of a hot Westbound, but never with a caboose.
2) The fuselages still travel to the Boeing Assembly plant in Renton over the south end of the old Woodinville Sub. ( Anyone know what the line is called now ??? ) And yes, they were a tight fit on the old through - truss bridge over the Cedar River in downtown Renton. I was told by a Renton Public Works official, during the reconstruction of the Rainier Ave. underpass, that the first 737 - 900 fuselage didn't make it through intact; thus they had to go around the North end to the plant.
3) Regarding the future configuration of the Wilburton RR / Highway project, I have my doubts that the line will be reconnected again. The state already has cried poverty,($35 million ), in not installing a temporary shoofly during the widening project. What's to keep them from doing it again ??? BNSF has already proven they don't need the middle of the line; King Co. Executive/ Bonehead Ron Sims wants to see it become a bike trail; so do the rich homeowners along the line. I do not put any stock in Tom Payne's ability to start a commuter train service along the line; that would have to come from local government. ( See above ) It could become another East Lake Sammamish court fight. Or maybe even ( my god no ), another SMART !!! Stay tuned...