The GM parts guys say the 2006 is unique to its year, which means the 2005 would have to be, as well. Looking up the part number for the 2008 harness (which I had to do because the one I bought came with a superseded part number) says 2008 only, which means the 2007 is unique, as well. Pontiac Grand Prix Harness. Engine wiring. Harness, eng wrg - 25838081 | Wholesale GM Parts Online, Louisville KY
I also think it's interesting that this part is good for the Super, but not the Impala SS of the same year.
