I'm installing a factory Nav system in my 2003 STS. I want to install the nav antenna in the factory location under the rear window shelf. Both Nav antennas listed by folks on the forum have leads too short to mount on the back shelf and reach the radio head. The parts catalog lists two different part numbers 88988035 and 88953291 (4450MM) but neither is shown/listed in any parts illustration. I'm inclined to go with the 4450 MM length cable, but it's quite expensive versus the other part number. Does anyone know which one is the correct one for my application? The part number listed in a previous thread, 19115355 is a fiber optic style cable and is for a 2005 STS not the 2002-2004 STS. I'm aware that most folks doing this mod mount the Nav antenna somewhere under the front dash, and this is fine but I want to mount the nav antenna in the factory location. Any help is appreciated.