ΔE 5.3, very close: most people won’t see a difference side by side. Grey Violet RLM75 is a little lighter than IJN Gray (Sasebo Arsenal).
Can I use Grey Violet RLM75 instead of IJN Gray (Sasebo Arsenal)?
Yes, for most jobs. Very close match (ΔE 5). Grey Violet RLM75 is a little lighter than IJN Gray (Sasebo Arsenal).
Can I use IJN Gray (Sasebo Arsenal) instead of Grey Violet RLM75?
The same difference applies the other way round: IJN Gray (Sasebo Arsenal) is a little darker.
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.