I purchased the extra guages for my FLHT and thought that I'd mark Celcius onto the face of the useless Air temp guage to try to make it at least show something I could relate with in Australia. I did it with a felt pen initially (texta??) I saw how ugly it was and changed my mind and rubbed it off with Metho.
Here's the interesting bit... When i was rubbing the texta off with the metho i also noticed that I was removing some sort of clear coating/paint??? from the glass lense. It never fogged up before but it sure does now!!!! I reckon HD put the coating on the lense to help with the problem
Neil