Thank you jnobles06 for the post. I own a 2004 F250 6.0 Diesel Crew cab and the info helped greatly in finding the factory code. On mine i removed the fuse panel cover and then removed the garbage bag holder to view and shine flash light through and had to reach behind where the fuse panel goes and move the white insulation pads to see the factory code. It was really simple to do. I needed a 8mm socket to remove the bag holder. i hope this helps anybody else looking for the factory code. Thanks Again.