You guys may think I'm totally nuts, but here's my thoughts. You would think "rubber is rubbber", right? On any Firestone tire I've had since the 60's I have had problems with getting them "Black". Whether they be blackwalls or whitewalls on a daily driver, or White Lettered on a truck, my experience was the same. The Black sidewalls were just awful. Same holds true for the reproduction Firestone Redlines I had on my 64 and 69 GTO's in the 90's.
Regardless of the era, or if they were new or reproduction, same situation. Any new trucks we've ordered in the past 15 years I've always stipulated "no Firestone tires". Never had any such problems with the Goodyears, either new or reproduction. In my mind - "What is the sense of getting the Whitewalls, Redlines or White Letters looking spectacular if the Black looks like crap?"
That is my "senile" opinion on that subject which may not make a lot of sense to some people
I've been using SOS pads on all my tires since the 69 RS/SS I bought new which had the White lettered Tiger Paws. Always worked great on Whitewalls and Redlines as well. I use a low sheen treatment (hard to find these days) on them every once in a while as I personally do not like the "high gloss" effect. However, my machine doesn't get a lot of mileage.
Just my two pennies worth guys.