The 5th wheel prep packages were in short supply in 2020 when I got my truck. My truck did not come with the prep package so I tried to order the Ford part, but it was out of stock with no estimated date of restock. I ended up buying the Reese underbed kit - it is pretty much exactly the same thing as the Ford piece - attaches in the same place using existing holes in the frame. You just have to drill the holes in the bed, and there are dimples in the bed floor that show you exactly where to drill. Hardest part is lifting the bed up to get the hitch frame in place. I used a 2 post lift to pick the bed up, but it could be done with a person on each corner - it is very light since it is made of aluminum.
I would have special ordered my own truck with everything I wanted, but who knows how long that would have taken to actually show up. As it was, I ended up getting the only truck within 500 miles of me that had all of the other options I wanted. Had to pay MSRP to get it, but at least I got it.
I still have not gotten around to installing the trailer wiring plug in the bed, but the trailer wiring easily reaches the plug at the bumper so it really has not been a problem. The most inconvenient part is having to unplug to open the tailgate and then plug back in after closing the tailgate, but that's not really that big of a deal.