I went ahead and did the rail delete today despite only having the rails. You can do it without those other two parts; however, I do see some issues that could arise by not using them, but we'll see. With that being said, like others, I used some butyl tape to cover the holes and then added 3-4 long layers on top of that so the rail will sit flush on the tape. Seems to work perfectly for now.
It looks daunting labor wise, but trust me it's not that bad of a job. Make sure you get an interior pry bar set! I did one side at a time, dropped the visor, the center console/sunglass holder, clothes hooks, dome lights, pulled back the A/B/C/D pillars, B is the hardest as it is held on with the grab handle (10mm bolts) and another 8mm bolt. After doing that on the left side I was able to pull the head liner down enough to get my hands and a socket wrench on the nuts. First side took about 1.5 hours to figure everything out and remove and install the new rail, the second side only took 30 minutes.
I would recommend getting the two insert pieces but if you don't want to wait or can't find them a good butyl tape will suffice for now. When I'm able to find them I'll install them on mine though. All in all it was definitely worth the time and effort. If anyone needs help DM me and I'll try to walk you through it.