I have seen a LCD tv screen that goes into the console. The thing is called a Convert-A-Console, made by Steel Horse. It replaces the factory console door with one that has a fold down screen in it. When not in use it spins around and drops into the door making it look factory for security reasons, this would solve your dilemma for the front, because of the overhead controls and sunroof. Price was $589 with VCP, if you wanted a TV tuner it was more. As far as the 3rd row seats go a drop down unit would work good there, and should be a pretty standard install. The console screen I saw was in a performance products catalog, no listing for Denali/XL but when I called to check on it they said it should be available by fall. The company is working on a door for the Denali/XL, because it is different from the Yukon/XL. Try these places.