There's a huge thread on F-150 forum about this. The member that did most of the research is also a member here. I can't think of his name.
I don't know if I'm the guy you're talking about, but I did it. There was like 10 articles each with a different set of part numbers. It started with a guy who took an XL f-150 with no lights what-so-ever that retrofitted his truck to have the ambient lighting. Of course that is a much more involved install, but I wound up buying a bunch of crap I didn't need, and eventually got it right. The whole install really isn't that hard. I linked a few videos on how to get the door panels off, and I gave my notes, including how to use a hot glue gun to hold the clips in place so they don't rattle (kill two birds with one stone). The lights really were easy to replace. Someone with the un-illuminated PRND should open their console and see if the light is there and just not plugged in. If it is not there, I am almost positive the connection for it will be there because it is tied into the rest of the harness iirc. If the connection is there, it might be as simple as ordering the light. If anyone lives near Augusta, and wants help with this, let me know.