ΔE 8.7, close: similar, with a visible difference side by side. Pacific Green is a little lighter, more muted than RLM 83 Dark Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Pacific Green is a little lighter, more muted than RLM 83 Dark Green.
The same difference applies the other way round: RLM 83 Dark Green is a little darker, 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 RLM 83 Dark Green on the colour wheel See Pacific Green on the colour wheel
All matches: RLM 83 Dark Green equivalents · Pacific Green equivalents