I have a 2008 Mariner with the audiophile system, i want to buy a used navigation unit and install it. Does anyone know where i would find the part numbers that would fit? I have the new bezel already and it seems most any ford radio/nav unit will bolt in other than the focus. Im just not sure about programming, THX, etc. Any help is appreciated

If the nav. unit is like an aftermarket one that just needs power to work, then you just need to find a compatible donor nav. unit. If it's just a screen and your Mariner was not set-up or programmed for that option, then you will have some issues.