I bought mine off the lot. Dealer gave it to me to take home over night; I drove it to work the next day, & by the end of the day I decided it wasn't going back. It was 99% what I wanted, with no wait for a special order.
If I could add any factory option I wanted, and wouldn't have had to wait a couple months or more for a special order, I would have added:
33 gallon fuel tank (they all should have this at no extra charge; if there's room, put it in every truck, can't cost them anything to do)
3.92 gears (major tow capacity increase, didn't do my research well enough, but I can get by as is)
Rear wheelhouse liners (should be standard on all of them, why is this optional anyway?)