5 years later 
having some dead pocket screen and dmg screen motherboard, i was searching for a way to transplant a mgb into a dmg mobo (just for fun) and some folks already did this ! 
even if some people tried to explain how to do it, the best way after all was this sketch :
https://chipmusic.org/forums/post/205616/#p205616
using the correct pinout and eagle to make a pcb, the goal here is to do the same PCB as this one :
https://oshpark.com/shared_projects/vr4ATKD8
but i wanted to make it fit into the shell.
finally I just use the FPC connector from the gerber file and I redid all the traces using the scan of the handmade draft drawing
here is the result after 1 hour of eagle pcb drawing and 2 weeks of waiting from oshpark :
the only issue is about the connector, the ones i ordered are made to have contact on the bottom side and the connector needed to contact on the top (like the connector on the pocket console). to correct the issue, i just remove the black "gate?" and made it upside down. the contact is not perfect but it work this way.
the dot on the soldered connector is pin 1 (important). 5 wires to solder, i use kynar wire.