My view is that the two shaped washers are there to accommodate lateral movement of the lower kingpin mount to achieve desired camber via the camber plate adjuster on later models with this adjustment. The washers allow the kingpin oiler bolt to tighten down squarely through a small range of angles. This can only happen accurately if the two washers are immediately under the bolt with their shaped surfaces facing in to each other and so working together.
Makes sense to me, but would this only become an issue if one wanted to actually adjust the camber angle? Then it might become a bit of a pain as presumably one would need to remove the reaction bar before doing the adjustment and refit it afterwards.
