I have a 2005 LQ4 6.0L with 30-35/k mile on it. It comes with a 4L60E Transmission, wiring harness, and ECM for this motor. It has everything that you would need to drop into any of your project vehicles. I have it on Ebay at this time. Here is the Link.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=120489692148&ssPageName=STRK:MESELX:IT