A518 assembly issue
 

I'm assemblying my A518 after tear it down for cleaning, adjustment and even change some friction discs.

Now I've the OD section separated from the main case and it just won't fit. I didn't disassembly the Overdrive gear train to avoid messing with the spring contained on it so I just don't know why the tramission intermediate shift don't completely fit inside the OD section

Any idea?