Replacing the t-stat on a 3.0. I found that 3whoever did it in the past put a wood screw into the bottom hole. Turns out that tha bolt housing on the engine side is broken and in trying to clean it up a little I find there really isn't much I can do with it. The bolt housing is broken beyond the point where anything will thread into it now. Any thoughts on what I can do to fix this or what do I need to replace?