The seats are held in place by studs, nuts and bolts.
The studs with nuts have a male torx end, which can be used to hold the stud in place while removing the nut. However, you'll want the stud removed as well, so try just removing the nuts first. If the stud doesn't come out, then you'll need to use a female torx socket to remove the stud.
The bolts utilize torx as well. You will need a male torx socket to remove them. I suggest using one which is 1/2 drive. Also, depending on the amount of corrosion you can't see, they can strip easily. So you may want to soak them with BP Blaster or the like.
I had to drill one out. I you do so, just remember that the gas tank is under some of them. Don't drill into that. That would be considered a bad day. Luckily I avoided a bad day. Not by much though.
Ford uses a foil backed tar tape to seal the holes, you'll want to use something similar.
Just locate all the studs/bolts and it's fairly easy.