Solar Flare vs Gold Yellow

How close are they?

ΔE 9.8, close: similar, with a visible difference side by side. Gold Yellow is a little darker than Solar Flare.

Can I use Gold Yellow instead of Solar Flare?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Gold Yellow is a little darker than Solar Flare.

Can I use Solar Flare instead of Gold Yellow?

The same difference applies the other way round: Solar Flare 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.