Agent Orange vs Light Red

How close are they?

ΔE 25.4, loose: different enough that you should pick on purpose. Light Red is noticeably darker, much more saturated, cooler than Agent Orange.

Can I use Light Red instead of Agent Orange?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Light Red is noticeably darker, much more saturated, cooler than Agent Orange.

Can I use Agent Orange instead of Light Red?

The same difference applies the other way round: Agent Orange is noticeably lighter, much more muted, warmer.

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.