Yes you're nuts.. don't do it!
Don't trade out your car for a 996turbo. They are nice cars, and I don't mind the headlights on the 996 turbo, but yes a 997 turbo's looks better. Another vote for not putting the headlight covers on it too. That doesn't look good in my opinion. Find a 996 turbo to go test drive, and drive your car there to do it. Maybe that would help you decide. I think the only thing you should trade that car out for is another "special" porsche.. any of the gt cars. Of course those are more expensive, but for good reason
Sorry I just spent an extra 50k of your hard earned cash!!