Rear seat mounting

[Blazerowner]

So I have finally acquired all the rear seat mounts to bolt in the rear seat. I still plan to recover the seat but want to get a little input on the floor. The prior owner did a pretty decent resto but the truck is still a little apart. All the rear bolts for the rear seat are removed from the floor. I know the rear four "legs" of the seat bolt to the floor and basically there are some metal strips that they sit on then one bolt goes into the floor through the mount. Mine has no strips and I am unsure what the PO did with them. I'm sure I can make some. Another issue is all the other mount points are gone. Basically just holes in the floor. Luckily I do have four heavy duty mounting bolts that the bolts for the seats bolt into. I'm pretty sure they are for the seat belts. My question is where do they go? They look like they go on the four corners of the seat since those holes are larger. Also how did the original mounting points for the rest of the seat go in? Was it just a bolt and nut or is there more to it? Last I remember the bed floor had mounting points and no climbing under the truck to hold a nut was necessary.