ΔE 17.2, loose: different enough that you should pick on purpose. Rucksack Tan is noticeably darker, more muted than Golden Griffon.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Rucksack Tan is noticeably darker, more muted than Golden Griffon.
The same difference applies the other way round: Golden Griffon is noticeably lighter, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Golden Griffon on the colour wheel See Rucksack Tan on the colour wheel
All matches: Golden Griffon equivalents · Rucksack Tan equivalents