Firstly to do the AWD conversion you will need the rear clip as well as the front.
If you keep ur stock GT tranny then you'll have a front wheel drive monster.
It will cost you a small fortune to get the AWD conversion done, people on this site and others constantly talk about it, but we've yet to see ANYONE successfully complete the conversion, with pictures and information.
In other words.. unless you have loads of money lying around to spend, an excellent auto shop to do all the work (or the knowledge/tools urself) or big bollocks, I'd suggest getting over it

I know Igotta and others will probably argue the point though.