I have a 99 1500 with the tow mirror that attach to the door panel in 4 locations (I call them spider mirrors). Anyhow, the mounting nut finally broke at one of the attachment points. It looks like the mounting nut was simply some threads welded onto a vinyl coated washer, and I was wondering if they can be replaced? If not...what are my other options?

 

You can replace it with what is called a self tightening nut (some call them other names), stainless steel is what you want. And they are available at most good hardware stores.