I came across this forum while working on my 68 Camaro. I installed a 05 LS6 pull-out from a CTS-V. It has been pretty straight forward, but there have been some challenges. With that in mind, I went ahead and purchased the factory service manuals (all three volumes). Although I am working on a classic vehicle and do not actually own a CTS-V, I hope that my purchase can help others as well. Please let me know if there is anything that I can look up for you. I may also be able to send scanned copies of pages that you need.
Just send me a pm and I'll get back to you as soon as possible.