Since Cadillac didn’t sell muscle cars, the honor for marketing the most opulent GM muscle car in the 1960s fell to Buick. Gran Sport was the moniker and – in 1965 – it adorned the mid-size Skylark for the first time. This enabled Buick to compete alongside the Chevy Chevelle Super Sport, Pontiac GTO, and Oldsmobile 4-4-2. The seller’s ’65 Skylark GS may be a work-in-progress as it pertains to the exterior, but it runs well, and the interior seems fine. Located in Broomfield, Colorado, this rubber burner is available here on craigslist for $11,500. Thanks for the cool tip, Mike F.!

While you could get a 300 cubic inch V8 in the regular Skylark, the GS came with a 401 “Nailhead” powerplant instead. That was the largest displacement that GM would allow its divisions to put into mid-size cars at the time. It was rated at 325 horses with a 4-barrel carburetor and produced 445 lb·ft of torque. That set-up would remain until 1967 when the Nailhead was replaced by a “regular” V8 at 400 CI. Not as popular as its other GM cousins, the Skylark GS accounted for sales of 15,780 units in 1965, of which 11,351 were hardtops like the seller’s car (and 7,670 had automatic transmissions, also like the seller’s entry).

We’re told this Buick’s odometer reads 38,000 miles, but it’s also conceivable the counter has turned over after 60 years. The seller says it’s a good running vehicle, though doesn’t mention whether any of the key hardware is numbers-matching. As you would expect, bucket seats and a console are provided, and the only noticeable interior flaw is a missing window crank on the passenger side.

The seller adds that the exterior trim was partially removed for a paint job, but doesn’t say if the latter was applied. Perhaps some body work is needed, and the roof appears to have a vinyl top or some other covering that almost looks sprayed on. The GS comes with Rally wheels with the end caps, but no mention is made of the age or condition of the tires. Is this a project car or one that’s nearly ready to be driven as-is?