HI, my name is*****'m a certified appraiser, and I'd be happy to help.
Your guitar was made at the Kalamazoo plant on July 10, 1978.
Unfortunately, the serial number doesn't tell me anything else. Is it an SG Standard, Junior, Special, or Custom? What finish? What pickups? Alternately, you can upload a photo.
If it's a Standard in a common finish and common configuration, such as cherry on mahogany with two pickups, the retail value would be approximately $1,800.00. But the value could vary based on the details.
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