Goes between the two bearing "Cones" as they fit into knuckle. Kind of assembled together and put in together as assembly. If you can find shop man etc, it will show it.
Looks like the spacer sets bearing preload.
I watched this video and got reminded why I avoided working on these! Just shows rotor replacement, but it shows some of the
reasons why people avoided taking these jobs on. A lot more labor complicated than the typical front 4x4 spindle/bearing set-up.
https://www.youtube.com/watch?time_continue=13&v=kOQPQfKAuHU
