aeromatic :
Thanks, I did check with Yuki web page, but not know their adaptor only support 2824 or also support 2836-2...
ubiquitous :
Thanks, very clear and I have a clue now to go next step.
Actually I did put a 2846 in my gen 1680 case with a adaptor ring, AND I cut the aftermarket 1680 dial feet glue on the 2846 movement. But the date window just a little bit lopsided not even notice. If somebody interest...I can post the photo.
Thanks you guys