The Type X option was available in 1994, through 1998 with the facelift, new side skirts, taillights, and rear wing added in 1996. Since the Type X trim option was available before the facelift in 1996, referring to the “Kouki/later term” options of the 180SX as “Type X” will always be incorrect unless the car is a true Type-X trim because all versions of the 180SX from 1996-1998 had the same front bumper and tail lights. By looking at the Type X model below, clearly saying Type X bumper and tail lights, make little distinction among early Type X  models that looked the same as every other 180SX before 1996. The rear valance was also available before the 1996 facelift. 

Feel free to flip through comparing the brochures below, you can see differences in options such as the airbag becoming standard in 1995 and the Type G being added in 1996. Thanks for stopping by, til next time.

-Ron

1994 180SX Brochure

1995 180SX Brochure

1996 180SX Brochure

1997 180SX Brochure

http://www.en.japanclassic.ru/booklets/10-nissan-180sx-1997-s13.html