Me and my uncle are going to buy a firebird that hit a tree this past winter and it needs a new front end. we dont like the 91 front end and want to change it to an older square front end. What all do we need to do and change for this conversion? ill post pictures of the front as soon as i get a chance

 

You will need the new front end, and impact bar because yours will not fit the older style. You will also need the front turn signals and a front wiring harness to get them working, or chop it up and splice it.

 

If the Firebird you are buying has the aero ground effects package, you will also need to replace the front ground effects where they meet the bumper, since they likely wont match up right, especially on the underside. The air deflector under the nose will need to be replaced too most likely, since the 91 model with ground effects is a 3 piece type with curved side pieces.

 

Welcome to the site.

Post some pics when you have a chance so we can see what you're up against.