F3 and F8?

"F3 is light green metallic. I could not find
F8 but I did find an EF8 dark green metallic."

On later year paint codes (70 & up I believe), the first letter is used to indicate the year of intro. for the particular color. E = 69, F = 70, G = 71....
T was used to indicate a corporate or standard color. eg. TX9 - Corp Black, TB3 - Petty Blue (although not officially called this)

HTH

Grant