Check this out... go to the 7th catalogue from the right, it's the GTS 2-door at the top, then towards the bottom of the catalogue, you can see all the variants, including the GTS-X.
I CAN read Japanese, if you have any questions, but zooming in on this catalogue just makes the print blurry. Just do a simple cross-check with the pics interior/exterior first, then if you still can't firgure it out, I'll call SuperAutobacs...