working space and monitor space are defined for white point D65.
Prints are optimized for D50 in a way that the appearance is VERY SIMILAR to the monitor.
I donīt think that you can directly shift the color temperature of neutral gray in an image by PhS,
but I am not a PhS expert.
The shift to D50 (red-ish look) or to D93 (blue-ish look) is done by a matrix multiplication
The accurate algorithm is available, but for simple tests this will be be sufficient:
(1) for D65--D50: multiply R by 1.1765, G by 0.9765 , B by 0.7218
(2) for D65--D93: multiply R by 0.8986, G by 0.9938 , B by 1.3602
By the way, this will cause clipping problems for Red (1) or Blue (2) .
Green is not much modified.
Perhaps it helps to adjust an image towards the one direction or the other.
Best regards --Gernot Hoffmann