I wouldn't treat PG listings as gospel, there's errors in there, generally not bad though.
Unsure of the question since the link you sent shows the Martinique blue bird decal for '78. This decal was likely a late addition as there was no blue decal listed in early '78 options literature and it carries a very late part number. Prior to that a Cameo white TA would use the charcoal decal, (as would the Martinique Blue TA).
Of course later it would become an option but only when using the blue interior which would not be common. Easy to check the build plate on the cowl to make sure it's actually a TA and that the interior was blue, then you'd think it would have to have blue decals, not just the bird.
But since your interior is already changed, and you don't want a blue decal anyway, the discussion is pretty much a non-event. It has clearly been repainted and it has the 1973 blue decal set anyway. So still not sure what the question was or what you wanted to know.