1966 Ford Mustang GT 2 Door Hardtop 20,000 Miles! Solid 289 4 Barrel K engine

Estate Sale: We have a bill of sale from its last sale in 1978 at 8,318 miles. Last on the road in 1983. We know the women who owned it back then, as well as the gentleman who just passed away. Placing it on Facebook yielded contact from one of its owners prior to 78 whom said he thinks the engine was rebuit to K engine. I'm not sure what that means.
GTIt is solid!289 171 HP4 Barrel4 Speed9 inch rearPower SteeringDisk brakesAll originalIt runsBody/ torque boxes solidNew Top / many other new OEM partsNo Title