with all these mods you definately should get Ls1 edit, get the full potential out of every mod. just find someone that has experience and might work a little magic.

if price is no option go take a look and hear this exhaust. I believe it is the most expensive exhaust setup with tips but definately worth it. Truly unique

http://www.gmmginc.net/html/chamberedexhaust.html

also NOS is a "bolt on" along with a super/turbocharger.I am sure he would be happy with any of those!