When I finished my FJ40 and took it out for a shake down run I had steering box problems develop where it didn't want to turn right. Entirely different box than yours... early J20 Saginaw box... but when I brought it back to the shop that had rebuilt it they found that the large nut on the input shaft had backed off allowing the valve body to spin. It put metal shavings all through my PS system and ruining the hydroboost and PS pump. Good move adding the filter. After that experience I will always have a filter on my PS system.
I like these simple in-line filters.
http://magnefinefilters.com/Magnefine-3-8-Magnetic-Inline-Power-Steering-Filter-R038M-P.htmThe hub swap looks good. What is the new width on the front axle?
