GET THE FACTORY SERVICE MANUAL!!!
As a Mechanic who worked in the industry and have done work for friends that have both haynes and chilton manuals, when it comes to troubleshooting and diagnosing problems the factory manual IS THE ONLY WAY TO GO!!!!! So many times has those manuals steered us worng and cuase more downtime and cost in the end! I have the factory service manuals for my truck and there is NOTHING i can`t fix or troubleshoot easily, The GM manuals are by far the best in design for ease when working on your vehicle. I t makes everything easy, trust me. they are worth their weight in gold!!!!!
P.S. i hate those "other"manuals with vengance.