Wouldn’t these frames also look somewhat different when projected, accounting for the warmth of the bulb etc.? Can you really just look at the frames themselves?
I personally feel the best course is to first replicate what’s on the print (at daylight conditions 5500K), and then adjust them to the desired color temperature. As NeverarGreat noted the reports on these lamps are conflicting, and a 35mm collector I know told me, that in his experience the difference between 1970s lamps and modern lamps is very minimal when projecting a print. Both lamps are in principle daylight-balanced, but I also believe carbon lamps tend to burn at a lower temperature as they age (becoming warmer), so that’s also a thing to consider.