Hello, thanks for taking a look. I have a 03 TrailBlazer EXT LS with the rear entertainment system, and I'm trying to take the output from my Aftermarket stereo to the rear dvd player so that I can play movies from a usb or flashcard. Is there any way this can be done? I would even be up to maybe totally replacing the RES with aftermarket if I have to but would like to use the built in stuff as it still works. I can run a Aux cable from the output of the dvd player to the back of my radio to allow for in car audio as well.