The K-Code Guide
VIN Decoder
Type the 11 characters from the fender apron or the warranty plate — or a Shelby serial. It decodes as you type.
Start with the model year
5, 6 or 7 — the first character on the plate
Where to find the VIN
On a 1965–67 Mustang the VIN is stamped into the driver's-side front inner fender apron, visible with the hood open, and repeated on the warranty plate riveted to the driver's door. It has eleven characters: the model year, the assembly plant, a two-digit body code, the engine code and a six-digit unit number. The fifth character is the one that matters here — a K means the 289 High Performance.
A GT350 carries its own serial on a riveted plate over the Ford stamp — SFM5S… for 1965, SFM6S… for 1966. The decoder reads both.
What each position means, with the full code tables, is in What Is a K-Code Mustang?. Warranty-plate codes — color, trim, build date, axle, transmission — are not in the VIN; they are decoded on a registered car's page.