Dodge built the 426 Street Hemi to satisfy NASCAR’s homologation rules, then quietly offered the same race-bred engine in showroom Coronets, and buyers who checked that option box created one of the rarest muscle cars of 1966. Estimates on exact Coronet 500 Hemi production vary by source, but all of them land in the low hundreds, with four-speed manual cars rarer still. A low-mileage survivor like this one is the kind of find collectors spend years chasing.