That's BIZARRE! My 91, my 92, all three of my 95's and my 97 came with the "pocket" and a single-din stereo.
The attached picture shows the set-up in my 95 2-door trail rig, as it came from the factory. I took out the factory radio, and put in an aftermarket stereo, and put an air pressure gauge where the cigarette lighter used to be, but you can see the factory set-up.
OH...WAIT! Mine have all been Suzuki's. It could be that on a Tracker, they did a double-din stereo. Either one will fit (the width is the same, and the height can accommodate either one).