Id assume you take 395 down to 84 and cross the bottom of the state to get to Kelso, or do you hit 18 (?) to I-5 and drop there? Im in Prosser about 45 min NE of Tri cities up I-82. If you get time around Christmas Im sure we'll be out wheeling a lot on snow runs and I usually have an empty seat.
It sounds like you have a decent grasp on the setup and you have most of the parts required as well. I use a spare tierod as the new draglink and I cut and sleeve it to shorten it to the correct length. For the steering box Ive thought about using a 2x box before but never tried it. Id think it'd work fine but may be weaker. One good thing is the pitman arm is a perfect match to a 4x box on the splines and it has the correct tierod taper for 4x tierodends. Its about 3/4" shorter so you can move your axle farther forward without issues and its got about 3/4" less drop to it as well.