[Count_Chockula]

To me it sounds like you didn't get the 'video' cable plugged back in all the way. In my experience, ribbon cables can be quite the pain! If you don't get it completely seated in the socket (even though they may look like it is) they will have all kinds of weird stuff happen... or just not work at all.
I would take the phone back apart and see if one of the ribbons has come loose, or disconnected some how. If that doesn't seem to be it, then you may have ESD'd it to death. To which there is no recovery from.