2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
You don't, on any vehicle if it's a front dash only unit, the automotive industry designed it as a safety issue so the driver's wouldn’t be watching a movie instead of the road. There are aftermarket mods, but you are on your own because they are designed around makes and models. Check the net, trust me it's there.
try the PAC audio model NU-GM3 it will allow for dvd in motion on the front screen and viewing of rear camera on demand . Normally priced around $240 I installed the PAC NU-GM3 on my 2010 lacrosse and it works as fine ,before it i tryed a NAVTOOL product but it was a disaster ,it didnt work and they new it wouldnt but sold it to me anyway ,the refunded the cost and still owe me for return shipping .