FM3 is the high-impact pink in Chrysler's 1970–1971 paint program — Dodge marketed it as 'Panther Pink', Plymouth as 'Moulin Rouge'. The color was introduced mid-1970 alongside the 'green' (FJ6 Sassy Grass / Green Go) and pulled from the lineup after 1971, with the heaviest production concentrated in E-body Challenger and 'Cuda orders. Total volume across both years and all body styles is small — FM3 is the rarest of the canonical high-impact set.
Earlier collector literature occasionally attributed Panther Pink to FK6; the Dodge Garage high-impact retrospective resolves this in favor of FM3 being the correct code. The Ditzler / PPG cross-reference is 71531 per the mymopar.com paint chart (historic reference — verify against current supplier formulary before mixing).