Yeah, I would definately run the audio from the DVD player (mounted in the CD changer slot in the glovebox) to the receiver and use the 4R's speaker system for the DVD audio.
As for mounting the receiver, that seems to be the only problem I have yet to address. I'm at a loss. I can't believe Toyota didn't leave enough space in that little flip down door under the A/C controls to install a HU.
What exactly is behind that door anyway? Is it something that can be moved in order to clear space for a HU? It's too low for the LCD monitor to be placed there.
I hope that once I can figure out all the logistics and install specs (locations, etc) I'll mount the DVD player myself (not a big deal) and leave the wires out so that when they take the dash apart for the HU install, it's an easy plug in for them. I've never installed one before but from the looks of the LCD monitors, it appears to be a simple install as well. Mount it and manufacture a surround (if needed) then connect the video out from the DVD player to the video in on the monitor.
So the only real install I would have to pay for would be the HU. And I suppose if I'm going to have to take the dash off for monitor install, I may as well install the HU myself too and save that money. I'm a bit timid to take that dash apart for fear of ending up with a squeeky dashboard down the line, but I guess if I'm going to undertake something like this I'm gonna have to get into it pretty deep.
I wish I could just do one of those carputers like Rando has, but I am clueless about how to build and wire it up. And I sure as hell wouldn't trust the clown at Circuit City Install to figure it all out for me.