The paint on the wheels wasn’t dark enough. The seat upholstery needed more embellishment. The instrument panel cried out for one last tweak.

For months, Ford (F) designers scrutinized the creation of their latest baby, the Lincoln C concept car of the future unveiled Monday in Detroit. Though the design was “locked” last spring, they found improvements they could make as the one-of-a-kind show car was built.

The result was revealed to reporters and photographers from around the world at the North American International Auto Show. Later this week, designers and engineers from other automakers will scrutinize the car to try to discern its secrets. Starting Saturday, the public gets a look.

“There’s nothing that gives you more elation than seeing the reaction on people’s faces once it rolls out,” says J Mays, Ford’s design chief, in talking about the C.

The Lincoln C is an attempt to show how a small car can be a luxury showpiece, thanks to elegant design and stylish details. It’s about the size of a Ford Focus, but sports a glass roof, center-opening doors and a powertrain capable of more than 40 miles per gallon on the highway.

There’s no indication that the C — a test-bed for ideas — will ever go into production. But it’s in keeping with Ford’s belief of late in a profitable future for premium small cars.

The C started life on paper and a computer screen. Then it became a full-size clay model. When the design passed muster, Ford turned over the making of the actual concept car to contract builder Aria Group in Irvine, Calif.

Aria re-created the outside by making a mold of the clay model. The interior was designed digitally. And the trick was getting the two to mesh.

Each concept car has its own “little quirks,” says Pete Gallagher, Aria’s chief project manager. In this case, it was trying to get the interior components to fit with the outside shell.

The project was helped along by having a longer build time than normal — about eight months — in which to solve the problems. In the fast-paced world of auto design, Aria’s work often involves last-minute rush jobs.

Ford designers also made changes during the construction process. At one point, they decided the car would look better with darker paint in the crevices of the wheels, said Freeman Thomas, director of Ford’s Strategic Concepts Group.

As interior design chief Gary Braddock watched the crafting of the outside of the car, he saw a way to add a flourish to the instrument panel.

The C had flowers and foliage etched into the seat upholstery after designers feared it looked too plain. Mays says the latest car designs are “so clean and modern, we’ve gotten sterile.”

The resulting C, Mays adds, is a Lincoln that can stand up to the classic simplicity of the brand’s most-admired years — 1939, 1956 and 1961. “You start to see the timelessness of a design,” he says.

The designers and builders alike were pleased with the finished car. “It came out beautiful,” Gallagher says.