I'm not talking about how easy or difficult it would be to swap out the wrong parts for the right parts. My bigger concern is/would be: if both the build sheet and window sticker list parts the truck clearly does not have, what else is wrong? How did this truck get through the inspection process (for which some trucks stay for weeks) despite clearly being built with the wrong equipment?
I agree with you that, if the only issue is the sidesteps, I'd have the dealer fix it and I'd take the truck. But, there is no way to know what else the factory screwed up at this point, and I'd be unable to trust the rest of the truck was properly built and/or inspected.
Put another way, let's say you go to a restaurant and order a pot pie with pancetta instead of bacon, no cheese, and pearl onions rather than Vidalia onions. If they bring the pot pie to your table with two big pieces of bacon on top, would you be confident that they made it without cheese and with pearl onions in place of Vidalia onions? I get that this is a ridiculous hypo, but it's the premise I'm getting at... if they missed something so easy to catch (like the wrong sidesteps), how can you possibly believe they got the small stuff right?