AMT-7 Light Blue vs Tanker Grey

How close are they?

ΔE 6.7, close: similar, with a visible difference side by side. Tanker Grey is more muted, warmer than AMT-7 Light Blue.

Can I use Tanker Grey instead of AMT-7 Light Blue?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Tanker Grey is more muted, warmer than AMT-7 Light Blue.

Can I use AMT-7 Light Blue instead of Tanker Grey?

The same difference applies the other way round: AMT-7 Light Blue is more saturated, cooler.

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.