the back seats do come out
I had a 96 that I owned for 4 years..... I know them very well.
On the back seat, there are indeed 2 pressure locks - they're white so if you lift up the front of the seat a tiny bit you can see where they are - they are located in the center of each seat right under the lip of the cushion. Press in on each one with a screwdriver or something and it pops right out. That's the bottom cushion, the back of the seats must be unbolted - there are (IIRC) 3 bolts that are clearly visible once you remove the bottom of the seat. For a convertible, the seat will pop right out if you lift up and back, for a coupe, fold the seats down and unbolt the lip of the back decklid, then unbolt the top of the seat - it should come right out then. If you still run into problems pm me. Btw, the guy who said you need a coat hanger to get the radio out was semi-correct. A hanger will do it, but the actual tool to do it is much more efficient, and is pretty cheap to boot. I've used that particular tool on about 5 different fords, they all have the same mechanism.