I spent a good 5+ years with the 3S platform. I started with an NA and then sold that and bought a RT/TT and modded the hell out of it. From the research that I’ve done and years of experience I can tell you that unless you plan on spending wayyyyyyy more then what you want to spend, you’re not going to accomplish your task. In my opinion, Sell your car and buy a TT if you love the 3S cars so much. In all honesty, there aren’t very many well modded Twin Turbos out there and the ones that are can be a ton of fun 
If you want to do something different or have the wow factor, sell the 3kgt and get an rx7 with a blown motor and put a V8 in it. But think of how many Twin Turbo 3’s that you see in Buffalo…its not a lot.