I bought a 20 year old Emperor clock that needed the weight chains re-installed and cleaning/oiling. Of course, I did not do enough research on oiling and I oiled it to much. I placed a couple drops of oil on the moon dial rod so it spread into the moon dial picture leaving a oil stain. To be honest I'm surprised how well clock oil spreads/wicks. Is there anyway of removing the stain or blending in the stain ?
I presume the picture is silk screened on. That being the case, I don't know of a medium that would not remove the ink along with the oil. Your best and most cost effective procedure would be to replace the small moon dial disk. A clock materials house would most likely be the best source.