R380 transmission rebuild

I am almost done with a R380 tranny rebuild:thumb-up:. My question is:- Why are the roll pins(spring pins) for the main shaft so short?:confused:
I assume they are there to hold the thrust washers in place. I have used 2 pins. I was also told that they are not needed. What holds the thrust washer retaining ring in place the oil gally insert. The photos show the pins in place and the split thrust washer and it's retaining ring. Does anyone have an answer for me thanks in advance:cool:
Attachment 10433Attachment 10434Attachment 10435

After looking through the parts book and my R380 Rebuild book, these were not fitted after Gearbox # -(G)410128J.

The later Mainshaft and gears no longer require the Spring pins.

I hope this helps.