Gibson's Firebird '76 model is a sort of upgraded Reverse Firebird III with bicentennial inspired pickguard logo. The neck pickup is a typical Firebird mini humbucking pickup, but the bridge pickup is a Bill Lawrence design with both bobbins rotated 90 degrees on their side. The bridge pickup isn't mentioned in the 1977 catalog listing for the guitar, but neither is the fourth and most uncommon finish color: White.
You can check out all the pictures and information here:
Gibson Firebird '76 White
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