LH526...Your going to have a real difficult time with this because there really is not any official colors for Pan Am, especially during this period. As you know, Pan Am's blue had multiple changes over it's history. Even in the 1960's, the 707's had varying shades of blue. Part of the problem was a/c were painted in various locations with different paint suppliers. I know this for a fact because I have been through this exercise trying to figure out this same riddle. Remember, things like Pantone did not exist back in the 1960's and color matching was not 100% accurate. On top of this problem, marketing departments frequently held information on company colors for the blue that may have applied to baggage stickers, timetables, stationery, etc., but these same colors were not necessarily what were on the aircraft. This is a common problem even with today's airlines. Good luck!