I tried to blow up that picture from Classic parts to see if the pattern is similar to the original material. The original has black color in the fissures, with the maroon color on the raised area. I couldn't blow it up enough to see it.
I have the Jim Carter maroon material and it has that dark fissure feature.
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission