Great deal on the diff! You could buy that and use it for the core exchange on a 4.10 diff, that way you can keep your own if you ever need to return to stock to sell the car.
The custom section 1 for relocated O2s means you could run headers (like mine posted for sale here:
http://www.zpost.com/forums/showthread.php?t=513178) with no software or sim and still pass emissions!