turbo AR

I had a S480 BW T6 and they are big. Worst thing is they are set up for a 5 inch downpipe. Hard to get that past the engine.
I would think with 360 cubes with the right heads, you could go with a T4 based turbo and only have to deal with a 3 - 3.5 inch downpipe, much easier.
The PT7675 turbo is very popular , lots of LS guys with 5.3's making huge power with them,8-900 HP with a 5.3.
Gives you an idea what that turbo is capable of .

http://ls1tech.com/forums/tags/pt7675.html