I am installing a Pioneer AVH-p6600dvd in dash system in a 2008 Expedition that had a 6 cd headunit with sirius radio and no factory sub. The head unit seems to get constant power but not ignition power. I call crutchfield and they said I need to wire the 12v ignition wire into a fuse somewhere even though I bought the harness from them they didnt tell me that. They said the factory ford harness theirs plugs into doesnt have a 12v ig/acc hot wire. Is there any better way to do this other that wiring to the fuse box.