Sorry if this a bit of a random question but does anyone know how to unlock the Toyota Celica GT-Four in Metropolis Street Racer? I'm at a point where I've reached the credits screen and am trying to finish off all of the unfinished events. The GTR events are proving particularly tricky in my gen 7 Celica so I'm trying to get the GT-Four. I tried looking for faqs for the game and one page suggested it was unlocked on a special event in chapter 13. I have completed the event (and the special requirements) but it is still not unlocked.
Thanks in advance