ΔE 16.3, loose: different enough that you should pick on purpose. Light Green RLM25 is a little darker, more saturated, cooler than Grey Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Light Green RLM25 is a little darker, more saturated, cooler than Grey Green.
The same difference applies the other way round: Grey Green is a little lighter, more muted, warmer.
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 Grey Green on the colour wheel See Light Green RLM25 on the colour wheel
All matches: Grey Green equivalents · Light Green RLM25 equivalents