thank you Automatico.
On Dw's Case, the Gen crystal need to be glued.
Unfortunately The case is not like MBW. And is not 1.1 build.
And GEN bezel insert need some reworking at the bezel too.
That's on my opinion is really BUD ......
DW 1680 is not 1:1 ( it not accept Gen Crystal and wrong bezel construction ).
Interesting will be to know if this 1680 is 1:1 .
http://www.ioffer.com/i/stainless-steel-submariner-1680-case-190586896