How to swap the seconds post on a DG4813?

[watchblog]

The 4813 movement in my Bell & Ross 03-92 died. I purchased a replacement movement (MT-DG4813) and spent a few hours swapping movements (1st attempt at swapping a movement). Everything went well, except:
The Hours, Minutes and Seconds posts in the new movement aren't as long as in the movement that came with the watch.

MOVEMENT THAT CAME WITH WATCH:

NEW MT-DG4813 WITH HOURS AND MINUTES POSTS SWAPPED (but seconds post is too short):

I figured out how to swap out the Minutes and Hours posts, but I couldn't figure out how to swap the seconds post. The watch is functioning perfectly, except that I can't install the second hand.

Can anyone please tell how to swap out the seconds post?

Thanks in advance.

 

[KBH]

I can feel your pain. I had the same problem swapping out a ETA 2836. You have to pretty much take the whole thing apart to swap the second wheel/pin. I ended up f'ing up the works and sent it to a watch repair guy who said, Sorry too f'ed up to fix.

Time to let the experts finish your project, I think.

 

[watchblog]

So you have to take the whole thing apart? I had a feeling that was the case. Do you know of any information on how that's done? I did a search, but couldn't find anything.
I have the old (screwed-up) movement, I can practice on it first (I have to take it apart anyway to get the longer second wheel/pin). If I find it to be too complicated, I'll have to take the new movement in for repair or live with no second hand.

 

[KBH]

Best I can tell you relates to eta2824. You have to take the rotor off the back side and start disassembling. You'll see the second wheel as you get into it. It would be a good idea to practice on your old movement first.