Final assembly of the Sergios took place at Pininfarina's plant in Cambiano, Italy. All have already been accounted for, much like the recently revealed Ferrari F60 America.
Pricing for the Sergio has not been disclosed but it is estimated to have cost around £2.5m. Each one of the six cars made was specified by their owner in a series of sessions at Ferrari's atelier in Maranello.
Sergio Pininfarina: A tribute to a legend
Fabio Filippini, Pininfarina's chief designer, said: "We asked Ferrari before even drawing the car if we could do it and Luca di Montezemolo [boss of Ferrari at the time] said we had all of his support.
"We decided it should be a mid-engined Ferrari because the first Sergio Ferrari was the Dino Berlinetta Speciale, the ancestor of all mid-engined Ferraris."
As well as retaining the core structure of the 458 Spider, the Sergio also utilises all of its interior components, although the cockpit has been reworked to include black leather upholstery with red stitching, a carbon dashboard and doorwell trim, and Alcantara seat inserts. The mechanical components, track and wheelbase remain unchanged, too.
The Sergio's bodyshell is also claimed to be stiffer than that of the 458 Spider on which it is based, as well as over 100kg lighter – resulting in an estimated kerb weight of around 1280kg.
Geneva motor show 2013: Pininfarina Sergio
Pininfarina's Sergio was first revealed in the UK at a gathering of Pininfarina models at the Hurtwood Park Polo Club in Surrey.
Previous Pininfarina one-offs based on Ferraris include the Ferrari F360 Modena Barchetta and the Testarossa Spider, as well as myriad show cars and concepts.
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