Ok, no takers so far. If anyone lands here with the same issue, the back of the seat cover is easy to pop open, but there are a couple of challenges to doing what I wanted:
1. the seatback of the 2nd row bench appears to be a solid slab of foam. Literally, 2 feet by 2.5 feet by 3-4 inches thick. Nothing like the front seats. So once you got the DVD headrest in there, there is no place for the cord that comes down out of one of the posts to go.
2. between the back of the cover and the foam is a solid sheet of metal. It has a few inch dia. holes in it, but otherwise solid from top to bottom.
3. While popping open the bottom of the back cover was easy, to get more than an inch or two of access (enough to reach my fingers up to barely feel the top of the seat back), I'd have to remove the entire cover, which would entail taking the seat apart.
So to accomplish what I wanted, I would need to create a hole in the bottom of the headrest post housing, to run the wire from there to the back of the seat, and hopefully line that up with one of the existing circular cut-outs in the metal. The posts either terminate into the foam (easier), or in some other kind of housing (harder)-- I couldn't see.
Sooo, at this stage I gave up, and will tell anyone in the third row to look at the TV's in the front row headrests.
Let me know if anyone has tips. I didn't want to jeopardize a nice, tight fit of the leather bench seat upholstry to do this, and just didn't have the clearance/access to mess around much otherwise.
