totally new to this so hear me out. We have always assumed my aunt's firebird was a 400 per her son who was previously working on it. the car has sat for years and I'm just digging into it again for her. From what I can gather it is not a 400 and he was attempting a clone, any way I still need a little help decoding its original options. The cowl tag has some numbers I can't seem to find meaning for. For example, above the "ST" line on the tag are the numbers 331 053. it is my understanding those a date codes for manufacture but the letter appears to be missing for the week, could these be accessory codes in a odd place or some other exception? below is the full tag as best I can read it: General Motors Corporation 331 053 ST 67-22637 LOR26559 BODY TR 259-Z S-S PAINT 2WG Any help would be greatly appreciated. Thanks in advance!