Raised white letters on tires question

[dave`12]

Just got the tires, the white letters not done well by factory. Well, I sprayed on some tire shine, and after sitting overnight, they turned brown.

I scrubbed them with gojo, and (second pic) they did not get much better.

Anyone know how I could make them nicer? Is there, perhaps, a special paint?

What would you clean them with, the Gojo was a fail, but don't want to destroy the white...

thanx