one of my license plate bulbs housing has a stripped screw. I have it in place but it is not sealing tight enough, and allows the elements in. When I went to change my bulb, it was wet on the inside and there was corrosion on the prongs. I cleaned them and the light was working that night, but shortly after it is out again. I think I need to replace the housing. Any insight on where the best place to find this part would be, and what the number is?