One of the results of making contact with my fence was that a marker light was ripped off. I began the replacement by doing all four at the same time. I removed the old rusty screws and was very careful to discard them. The new screws will be stainless so that they will not rust. I will save the lenses just incase and save the bulbs for when the new ones blow out.
There was a great deal of putty and some deep corrosion where the old marker light had been. That brown on the outside of the marker light shadow, was a real bitch and required some serious elbow grease.
I doubled two cotton buffing wheels together on an extra long spindle and went at it with black rouge. I buffed for about 5 minutes and wiped it all down with mineral spirits. Next I used brown rouge and wiped it down, followed by the green rouge. The surface now looks like a mirror. I would say that it took about a half hour per light to prep the surface for replacement. Tomorrow I will install the new marker lights.