Most AWD PIU do not have a terrain mode selector. They do have specially tuned AdvanceTrac full-time AWD with electronic stability control (ESC) system tailored to emergency driving.
Some features were options that could be added to a PIU that were often used for Investigators unmarked cars, and for Administration vehicles. I have seen PIU with the factory console, carpet, and complete front/rear cloth upholstery.
The pictures above are from AsiaMotors in Chicago, and they have vinyl seat covers they install to cover up worn or damaged factory upholstery. On the AsiaMotors website you can download the original window sticker and see all the features and installed options as built.
If you do some GoogleFu you can find the Ford Police and Special Services Vehicles brochure that describes all the features, available options and special details of the PIU.
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