ΔE 10.8, fair: the same colour family, but not a straight swap. Phalanx Yellow is a little darker, more muted than Sunpetal.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Phalanx Yellow is a little darker, more muted than Sunpetal.
The same difference applies the other way round: Sunpetal is a little lighter, more saturated.
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.
See Sunpetal on the colour wheel See Phalanx Yellow on the colour wheel
All matches: Sunpetal equivalents · Phalanx Yellow equivalents