In 1963, the old magenta and yellow couplers were used which gave that Dmin problem and fade. The process itself could contribute to cyan fade if not done properly. That could have been either the P-122 process or the Ektaprint C process.
Just says "KODAK SAF.ETY FILM" on the neg.......... and the neg hasn't faded much, if at all, over all those years as I have proved.
Those suggesting pulling color negative film several stops: Have you ever done it? The C-41 developer time is only three and a quarter to three and a half minutes. Not only is it incredibly difficult to accurately time a pull, but anything more than a stop or so, and the color goes haywire. Anything over 1/2 stop, and you lose a lot of control over color balance when printing. IME, you can go as far as one stop and still get OK color, as long as it is for this sort of thing.
In short, overexpose like Mark Antony said, and pull 1/2 stop or 1 stop is my suggestion. Even then, the film will likely be too "good", and you will need to manipulate the picture a bit later.
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