I would try some brake cleaner,simple green, denatured alcahol! Is it some kind of tar! You might try some bug and tar cleaner and also at the hardware stores they sell some stuff called GOO GONE you might try that .All of the things I suggested is pretty easy on paint also. Hope you get it off easily.
That looks like the ignition box got to hot and the bottom of it melted. I have the same stuff on mine and it is where the box has always been mounted. I know how sticky it is. Have you tried a heat gun and a scraper?