Previous batches of these bushings had all the same size washers. It was just the last batch of four sets I got which came mismatched. When installing a set in my car I questioned the need for replacment washers at all and suspect the stock ones which are all the same size (from memory) would do just as good a job. Solid bushings such as these and the TWM's simply fill the space left by removing the old washers, limiting any movement / stress that may occur by doing so (as far as i'm aware). I know others have removed their bushes completely which I would say is less advisable. The washers don't have a function as such other than being a seat for the four bolts holding down the shifter. My apologies for any confusion.
I didn't realise it was you phil.
Turbosmart SU BPV // MZR Performance Intake // Medieval Inlet pipe // Medieval rear engine mount // RKM shifter Bushings // SLS Racepipe // Eyelids