Bf Goodrich brown walls

So I finally had the need to go after some "brown" on my BFG white letters on my 71 Demon 340. Somewhere on this forum someone showed the chemical rationale why acetone was the proper "solvent" to use. So I gave it a try with a little scotch-brite pad. Using very little elbow grease, the brown was nearly instantly wiped away! I don't think the letters have been this white even when new (tires are roughly 2 years old now). The brown wiped off easily and without issue or alot of scrubbing.

Now how long will it last/stay white? Dunno. But given it was this easy to do, it can almost be considered routine maintenance if it does come back in a few months. Just wanted to pass this along FYI.