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Prepare to loose some skin. As RollaMo stated you use either the aftermarket glass "ZR1" style or the 91 up bumper with the third stop lamp in the tail. They bolt on the same as your old bumper 6 10mm nuts on each side, and 7 7mm screws along the top, two 10 mm at the license plate and two more under the rear lower lip(numbers are appox.). Some trimming of the bottom corners of your old "egg crate" inner structure may be required. Remove the inner fenderwells and all the rear lamp assemblies to access the nuts/screws. A word of caution, the replacement bumbers usually are a pain to align to the rear fenders some time, and sometimes there is an 1/8" difference in the width due to shrikage of the 91up unit or the way they make the fiberglass.