Fenders and hood are the same. But everything else associated with the front end will need to be swapped: bumper cover; ;both headlights need to be swapped to older style. You can't just change the "lids" because the mounts (which are built-in to the bottom side of the lid) are different between the old, large rectangular headlights and the newer, smaller 91-92rectangular headlights. You can't just change the bezels because the headlights are physically smaller on the 91-92's & the bezels won't fit around the larger headlights of earlier years.
Also, you need the long bracket/brace that bolts to each fender and extends across the front of the car, holding the top of the bumper cover. It is 91-92 specific as well.
Turn signals and foglights(if applicable) and the wiring to them; bumper support and 'honeycomb' impact material; and underside airdam parts.
It's easy to do, but it's not cheap.
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