What does the paint inside the trunk lid look like? Often times it is bright and unmolested. Most automotive paint companies can scan the original paint and get a almost exact match.
I guess my question isn't so much about the factory color, I know the factory color calls for what was "Light Blue" in 1965, but rather if it's reasonable to believe my line of reasoning that suggests the current color is a "close" match, but not quite.
The short version "Am I reading these paint codes and cross references correctly?"