Mine was done over this past winter
Computer & wiring harness are a must, you'll also need the sensor pac that under the passenger side fender wall, vacuum tree & lines, it would help to beef up the shocks and struts. You can leave the stock V-6 rear end in for a while, but you'll need to pull gauge cluster, the tach & speed ratios will be off until you swap rear ends. You'll need the exhaust from a GT. Your best bet is to get a junked GT and strip it!