Originally Posted by sledtrash
I have a 1999 GMC 1500 with a automatic tranny I want to put a 5-speed, or 6-speed tranny. where can I get the information that I need to get the swap configuration figured out...... any help I know that this is a car forum but any help would be appreciated.
Start with the 1999 Chassis Service Manual. Note how there are pages of wiring diagrams. The problem is that the EFI computer uses inputs from the trans. At a minimum, you'll need the ECU and harness that goes with the manual trans for that year and model.