Just did my '16 2500. Other than some scraped knuckles, it went together like a charm. It sure would be nice to be left-handed.
I took out the top glove box for better access and view. After dropping the bottom box, there's one nut underneath the top one toward the driver side. 9/32 socket. Then the top box will pop out - it's got a few trim clips holding it in just reach around back and give a good push.
The plastic cut-out is thin, and heating it with the wife's hair dryer helps a lot. You do need to cut out the two little notches to the right and left of the bottom part of the "T" so the prongs on the new door slip right in. My door went on and latched tight with no problem.
Getting the filter in was a bit of a challenge with the dashboard in the way. And it's fairly rigid for a piece of paper. I used a Fram fresh breeze. The longer side of the filter runs from front to back of the truck, and the shorter side of the filter goes from driver side to passenger side. You kind of have to put the passenger side in the glove box area first, then the back corner of the passenger side into the slot, then twist the rest of the filter in then it will slide all the way into the slot.
Door was $13.95 at the dealer. Fram filter CF10729 was 19.95 at Farm & Fleet.