Your radio should have four holes in the face. Two on each side on the front. They are around 1/8" in dia. You can fashion two "U" shaped thingys out of wire that is fairly strong. A "heavy duty" coat hanger. Then push the two "U" shaped tools in the holes, one on each side. You have to release the springs that hold the radio in. This is a little tricky, so work with it here. Once you get the radio released, it will pull out the front and then you can unhook the wires.
2005 F150 SuperCrew "King Ranch"
1986 LTD II
1964 Corvair Monza