Hello,
The two machined and hardened "thrust washers" are used at the top. Be careful to align the notch in the lower of the two upper thrust washers with the pin in the king pin housing. Also make sure the four oil grooves in the one thrust washer face the opposit thrust washer. The correct shim is selected for use at the bottom of the assembly between the king pin housing and the knuckle (lower trunion). You will need to try or adjust several to find the correct shim. At times I have had to lap down shims. At other times no shim at all will be correct. It varies with each car.
Remember you need some up and down clearance, there is a spec. If you choose a shim too thick the king pin will bind when you tighten down the bottom 22mm nut. This will make the steering too stiff and it will it will not center automatically after a turn. Choosing a shim too thin will allow to much up and down free play and can cause noise on bumpy pavenment.
Since the lower portion of the king pin is tappered, the clearance will diminish as the nut is tightened so tend to leave a bit more clearance before torquing. Before moving onto the other side make sure the king pin and steering move freely!
These assemblies are frequently incorrectly assembled by others. Make sure the position and sequence of all the thrust washers and shims are correct. Pay special attention to make sure that the pin in the housing is aligned with the slot in the thrust washer or your shim settings will be off.