New to site need Help with build up... what to do?!

Hi everyone im new to the site I know there is a place to introduce myself but this should do fine. I have a 2006 reg. cab 6 foot bed 2wd with a 5.3. I have a whipple supercharger 8psi, headers, true duals, ss mufflers, funtional keystone customs ram air hood right in to a huge K&N. Im not running any whipple electronics, i have stock gears (323's) the thing is pretty sick ill get some pics up soon. I've been reading over this site for a while now and i finally got around to joining. Everyone here seems very cool and im glad I can be apart of this site. I swear i have bowties in my blood!! hate jap.. well.. everything.. the usual chevy guy, you guys know but anyways I have a few questions for you seasoned Chevy Veterans. I can get my hands on a LQ4 6.0 and a 4l80 cheap. (4l60 and whipple don't get along much) So my first question is could you guys tell me the differences of the LQ4 6 vs my 5.3 besides the obvious. Is it really worth the extra dough? If i do go for the 6.0 id like to go fairly nuts on it. If you guys could give me your opinions on the 5.3 vs the 6.0 first then we can talk about the build up alittle that would be great!