Pardon me for stirring up this old thread but I came across some additional information which may be helpful, especially to newer Uplander owners who may face similar circumstances.
I recently purchased a used 2006 Uplander and it came with a remote control and no headphones. I looked through this thread to get a better understanding if my van should have the wireless headphones or not. It is a LS EXT. My RPO code is U56. I called my local dealer to see if they knew if my van should have come with wireless headphones or not. The parts guy asked for the last 8 digits of my VIN # and then looked it up and told me that my van should have come with the wireless headphones.( At that time I also checked on their price, $130 for each one

) I found a practically new set with remote on an eBay auction which I won for $80. So if anyone is in doubt if their van should have the wireless headphones or not, give your dealer's parts dept. a call and give them the required digits of your VIN#. And after owning GM vehicles for over 20 years, it doesn't surprise me that they would make some vans with wireless headphones, and some without. I think it's a marketing tool to get people to purchase a more expensive vehicle to get the options they want.