Question [Q] Korean LG-SU640, what method should I use to root?

I was told this was the same as the US Nitro but I'm not sure. Bottom line is I would like to get it unlocked. Whats the best method. Heres the about phone info

LG-SU640
Android 4.0.4
Kernal version 3.0.8-perf-00001-g6760a11
Build number IMM76D
Software version LGSU640-00-v20f-feb-14-2013-15:43:24

Cell phone carrier T service? not sure but the logo is a T