T720 Screen Replacement

I will go ahead and answer my own question since I found instructions
online which naturally weren't 100% clear until after I did it myself.

The hinge must indeed be taken apart. Do this with the phone folded and
fold it back before reassembling. On the end of the hinge where the
antenna is push out the clear plastic that forms the status light
(flashing green or red) if you enable it. This literally just pushes out
from the inside out and when all done you can shove it back in, outside
in. The hinge is taken apart from this same end, which is the spring
loaded end.

This end has a button of sorts which comes into that same space where the
status light thing was. If you push against it and its spring pressure
you can tilt off the one half of the phone from the other and then slip
it easily off the non spring end. This is the part I wasnt clear about
from the other instructions. The direction to push is *across* the
hinge, from the side of the phone with the antenna to the other side.
Like pretend you were hold the phone (closed) battery side up, and
antenna at top left. The place to inside that tiny space where the
status light thing is and the direct to push is towards the right. To do
this you should find or make a tool with a L shaped bend on the end. The
thing you are pushing on is a Y shaped lobe and you must push it in
enough so that it clears the inner end of the outer half of the clamshell
spring.

Once apart it will be obvious about dealing with the ribbon cable.

To reassemble assuming you had the phone folded when taking apart fold it
up when reassembling the hinge spring. Slip together the non spring end
and tilt the spring end in pushing the button in until the pieces are
togehter and the button thing seats properly.

Hope this will be helpful to someone attempting the same repair or
replacing the housing etc.