The obvious source is Dr. Brett Johnson's The 911 & 912 Porsche, a Restorer's Guide to Authenticity. According to it, the exterior colors available in 1965 were:

  • 6401 Slate Gray
  • 6402 Ruby Red
  • 6403 Sky Blue
  • 6404 Light Ivory
  • 6405 Champagne Yellow
  • 6406 Irish Green
  • 6407 Signal Red
  • 6410 Dolphin Grey
  • 6411 Togo Brown
  • 6412 Bali Blue
  • 6413 Black


My car, 301382, and Jacques 301379 are both 6405 Champagne Yellow.

Also, it's pretty clear that the first two digits of these color codes are the year this set of colors was introduced. 66xx color codes wouldn't have been used in 1965.

davep has records showing a few cars with 64xx color codes after July 1965 and a handful with 66xx color codes before July 1966.