I think it's a lot of trouble to go through for only about a 50 hp increase, and I'm not even talking about getting into the computer. (Talk to Rudy about that).
You're adding weight to the front end, so it will have an effect on your handling, and I don't think there are any more performance options available for the 4.3 engine than there are for the 3.2.
Of course I don't know how many miles are on your current engine, but unless it's over 250k, I wouldn't even be concerned.
There have been several Crossfire engine swaps performed here on the forum, and with the exception of the 3 performed by Rudy and Tazz, I can only think of one other that was considered a success. The others seemed to be completed, and then put up for sale soon afterwards. Leading one to believe the end result was less than desired.
You're young and full of energy, and I have no doubt between you and your friends you could get the swap completed, but if it's your only ride, be prepared to make other transportation arrangements for awhile. Because getting everything sorted out will take some time.
I just think once you get the car completed, you will find very little "seat of the pants" improvement over what you currently have, that's all. Just my two cents. Good Luck with what ever you decide to do.