IPS makes a good TT kit. Its a few people on the forum with it. You'll have to keep the boost within reason (I wouldn't go over 650hp) on stock motor.
Kit Details:
http://ipsmotorsports.net/ips_motors...t/g-65338.aspx
I just installed the TTI/Granatelli twin turbo kit. I believe the baseline numbers on a LS3 @ 8psi makes 615wrhp/613lbs torq.