Im not sure if you picked mounts yet but like someone else said dirty dingo has a good reputation, I've been looking to do this swap myself except with 04 gto ls1 and a few good companies for wiring are currentperformance, speartech, nelson just make sure to research the companies you pick see what people say about them.
I don't know what engine your picking some ls are a little different on the accessories but for some relocation brackets in case you find out something won't fit try
http://www.kwikperf.com/index.html