Fog Light Assembly

I have a 98 Explorer Sport. Behind the square fog lights, there is some sort of assembly. I was told, that Ford was trying to get rid of parts from their 97 model, so they put the old parts on the 98 until they got rid of the extra. Anyway, my question is can I take the plastic cover off of this assembly and replace them with another plastic case or do I need to buy the entirely new assembly? When looking under the truck, I can not seem a way to take just the actual case off (unless the entire metal assembly comes off).

Here is a picture of what I am talking about:


http://www.slickcar.com/productdetails.asp?ProductID=4503

 

[Bill Kemp]

I think there is a bolt on the top or the back of the plastic fog light that goes thru the metal bracket that holds the light on the bracket. Remove the nut and the light comes out....