ΔE 6.1, close: similar, with a visible difference side by side. IJA Light Grey Green is a little darker than Gray Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). IJA Light Grey Green is a little darker than Gray Green.
The same difference applies the other way round: Gray Green is a little lighter.
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 Gray Green on the colour wheel See IJA Light Grey Green on the colour wheel
All matches: Gray Green equivalents · IJA Light Grey Green equivalents