The only reason I think they are similar is that there is physically only a limited amount of width avail for the widened gears in the MY02+ and GC8 STi/R/RA gearboxes.

The 4th gear thrust washer is the identifier. If the thrust washer is approximately 3mm in thickness then you have the wider gears. If the thrust washer is thicker than you have the narrow (Pre MY02) gears.

Steel Billet Selector Forks in the STi boxes are good too as opposed to the aluminium ones in the normal WRX.

J

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