Gehenna's Gold vs El Dorado

How close are they?

ΔE 18.7, loose: different enough that you should pick on purpose. El Dorado is noticeably lighter, much more saturated than Gehenna's Gold.

Can I use El Dorado instead of Gehenna's Gold?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). El Dorado is noticeably lighter, much more saturated than Gehenna's Gold.

Can I use Gehenna's Gold instead of El Dorado?

The same difference applies the other way round: Gehenna's Gold is noticeably darker, much more muted.

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.