Changing the display would only work if the mainboard of the beo5/6 is
in the screen, and to my knowledge it's not the case (correct me if I'm wrong, I've not unmounted a Beo5 yet), otherwise :
-I can't see how the display could be fed with the correct signal, i.e. the 3 buttons at the bottom are "physical" sensitive buttons on the Beo5, and are replaced by icons on the Beo6. How could you program the Beo5 to display those buttons?
-You won't have wifi
-When connecting to a PC, the Config Tool will still see the Beo5 as a Beo5, not a Beo6 (hardware and firmware are a lot different between Beo5 and Beo6.
So please explain that a little bit more... If the mainboard is in the display, it would work, but that would also mean that the Beo6 display part is really expensive... (if you know the list price of this part, tell us!)