Looks like this pic? The following is from CRG data.
The LOS (Los Angeles/Van Nuys) body scheduling code is a letter followed by one to three digits, e.g., F103. Based on data analysis only (there is no GM documentation yet available that describes this code) - but with consistent application to thousands of datapoints - CRG believes the code was used by LOS Fisher Body (and other plants that built multiple carlines) to aid in scheduling the body build order. http://www.camaros.org/numbers.shtml#CowlTag