Cleaning dirty Rek O Kut top plate: what is best method?

[monkboughtlunch]

What is the best cleaner and/or cleaning method to remove embedded grime in the paint of a Rek O Kut top plate?

 

[BassKulcha]

(There was a thread last year on what *not* to do—I think the OP polished off the top layer believing it to be solid...)

 

[JFRACE]

Have you tried lighter fluid or isopropyl alcohol?

 

[monkboughtlunch]

Have you tried lighter fluid or isopropyl alcohol?

Tried isopropyl alcohol in a couple spots. Seemed to make an improvement. But was unsure if there is a better approach that is safe for the paint.