The idea came from someone else on here - sorry, can't recall who right at the moment - but he had some old motorcycle tail lights mounted on the fenders if I recall, which looked great. So I picked up a nice pair of correct repro Lucas 1130 indicator lamps for a MG TF with the red dot lens, and have been pondering for a year now installing them at the tops of the fenders. Would require a bit of a curved gasket to make them sit correctly on the fender. Perhaps a good job for a 3D printer? I think they would look cool, and help define the width of the car a bit better at night. But I like the clean look of the fender tops also, so have not got 'round to it yet...
Here is what an original one looks like - on my '55 TF:
