OXFORD — It’s safe to say that Jack Greenleaf is an automobile enthusiast — one might even call him a nut.

His garage is a galaxy of automobilia — license plates from every state and province cover the walls and rafters, antique gas pumps stand near the doorway, and a glass case holds hundreds of spark plugs, joints and shocks — the culmination of six decades of collecting.

However, the real attractions are five vintage cars in pristine condition, including his beloved 1931 Auburn convertible. It’s a twin of his father’s car he damaged while on a date with his future wife.

At 81, Greenleaf has spent a lifetime restoring rare cars he’s found hidden in barns, forgotten in garages or battered through use. They are gems found solely through word of mouth, he said. 

The son of a mechanic, he worked on car electronics professionally for most of his adult life. At his King Street workshop, he overhauls vehicles thought long-gone, meticulously restoring the engine, frame, interior and paint.

It’s not an exaggeration to say that his work is museum-quality, although he insists that every car he restores is road-worthy. 

“I don’t like the newer cars,” Greenleaf said. He won’t work on anything made past 1975.

“The old ones have character; you can tell the difference,” he said. “Today, you’re going down the road, they all look the same.”

After this weekend, however, Greenleaf’s collection is going to get a little smaller. Eight hundred lots, including three cars, are scheduled to be auctioned off in South Paris and online beginning Saturday morning.

Parting with even a small bit of his collection is hard, Greenleaf admits, but at his age it’s time to consolidate a little. 

Age hasn’t dimmed his energy, however. His eyes light up as he describes his treasured collection. When he starts relating his quest to acquire a licence plate from the Canadian Territory Nunavut, his excitement is infectious. 

Through the years he’s collected automobiles, Greenleaf has also collected stories. His 1927 Auburn convertible was used as one of the main cars in the 1974 film “The Great Gatsby.”

“Unbeknown to me, they shipped the thing over to Europe,” he said. “It came back from Ireland in horrible condition. They took the whole front end of it off to mount cameras and so forth.”

Consequently, he sued Paramount Studios for damages — and won. A clause in his contract required the company to return the car in the exact condition it left, and the motion picture giant quickly settled the case out of court. 

For a short period, Greenleaf owned President John F. Kennedy’s last personal vehicle, issued for him in 1962-1963. He found it, abused and beaten, in a dive bar in Long Island and rebuilt it from the ground up. 

Within a few years, the car was nabbed by a connoisseur of famous cars in Colorado. After his death, Greenleaf learned the car went for $80,000 at auction. A few years later, it was sold for six figures, Greenleaf said. 

After all the decades, Greenleaf is still working on restorations for private clients. The chassis for a 1929 Cadillac is sitting in his workshop, ready for its restored engine and body. A 1937 Packard he completed a few years ago stands nearby. His work on that car was awarded a perfect 100 points in the classic car rating system. 

He’s nonchalant about his perfect score — after all, perfection is what he aims for.

“What’s the sense of going to the Olympics if you’re not going to win?” he asks.

The Greenleaf auction is scheduled for 9 a.m. at the Four Seasons Function Center on Route 26 in South Paris.