Did the counter 5th gear fit on the Counter shaft 5th bearing Journal?
Just curious.
The counter does fit the bearing.
UPDATE:
You will also need these parts from the R452:
33395-35041 Sleeve
33318-35050 Spline
33394-35040 Key x3
33392-14020 Spring x2
BTW, the 33336-25030 5th does not just slide on the splines. It may need to be pressed on. I have not installed this yet, it will go on after my turbo install.