that'd probably be the original engine number, which is what most areas used for registration back before the door tag serial number 'vin' became the govt mandated many digit VIN
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics
