is that a JDM or USDM cluster? I would say if it's a USDM, and from looking at the wires, that it is the airbag one...No wait. its not that plug...I will have to go out and look at mine again and see if I can figure it out for you...
Side note: if it is the JDM cluster it could be a hookup for another option on the cluster not offered in USDM but not sure sinc eI haven't personally put a 92-95 JDM cluster in...Yet..
Good luck...