Note there are at least three variations to the Factory recording numbers on the frame.
1. Frames having "low-range" numbers have ONLY the VIN stamped on the LH headstock.
2. Frames having "mid-range" numbers continue to have the LH numbering stamped in the headstock AND an adhesive aluminium sticker on the RH headstock. This sticker has NO mfg'r date.
3. Frames having "hi-range" numbers continue to have the LH numbering stamped in the headstock AND have a tag riveted to the RH headstock, including a mfg'r date.
A. Frame 1683 has an original appearing adhesive tag, IDENTICAL to 4540.
B. Frame 4540 has an original appearing adhesive sticker with no mfg'r date. (identical to 1683)
C. Frame 6623 has a riveted tag with a mfgr date "9/69." (I owned this frame.)