What you need is the Kodak color print viewing kit, publication # R-25, I doubt this has been made in years, but there may be some on fleabay and other similar sites.
The actual filters are 5M, 10M, 20M, 5C, 10C, 20C. 5Y, 10Y, 20Y, they also have them in red, green and blue. You look at the print through the filters, until you see which one looks best, for negative materials you subtract the amount of the filter, for positive materials like Ilfochrome, you add the amount of the filter. You could view the print against the slide, but there is no guarantee that the colour balance in the slide is perfect, so it's often better to judge a print as a print, in the same kind of room lighting as where it will be displayed.