He looked back at the serial number: .
It was the chaotic era of the Norlin corporation. They were stamping numbers without strict logic. gibson sg serial number identification
"137" was the code for CTS pots. "73" was the year—1973. "4" was the fourth week of the year. He looked back at the serial number:
But the '8'? That meant this guitar was the 8,1075th... no. He checked the "FON" (Factory Order Number) logic. Sometimes they used the first digit for the year, sometimes it was just random. "137" was the code for CTS pots
The real identification comes from :
Then, he found the explanation on a forum deep in the search results. “During the Norlin era, serialization was chaotic. In 1973, it is not uncommon to see numbers starting with '8' or '9' in the 100,000 range, often overlapping with previous years.”
During this decade, Gibson used a confusing mix of 5- to 6-digit serials, often repeating numbers across years. The general guide: