Make sure you work out your trade in value seperate from your deal on your 08 FX4. If you have a Car Max in your area, they will give you a trade in quote for free. You can even sell you car to them and not buy a car from them. I always do that first before I got to another dealer so I know where to negotiate my trade.
So your getting a Screw with a 6.5 bed! Thats a long truck! that wouldn't fit in my garage.