[William]

The body number has nothing to do with production or production scheduling. I have maintained a reverse-engineered production schedule for many years. GM released the first and last VINs built for most months so that's what it's based it on. Van Nuys is somewhat easier to figure as there are some VN BBCs around and they were dated when printed. That date was when final assembly began; the body was already done. The few Norwood BBCs I have seen do not have dates so it's an educated guess. Firebird was mixed in with Camaro production at Norwood starting about the 3rd week of April and that makes it tougher. The overall rate stayed the same but the mix varied.