If You have PhotoShop, look this colour swatch:
It also showing "different" colors 74 and 75, wich is most dobtfull now. Usually most modellers use "distorted" 74 and 75.
74 as "Dark gray" and 75 as "Medium Gray".
But they forget that 74 was "Green Gray" and 75 was "Grey Violet"
You may find correct in this palette.