Purely as a design exercise, aimed at keeping demand for Lamborghini's Miura on the crest of a wave, Nuccio Bertone assigned Marcello Gandini a styling project to create a Spyder version of the Miura, commencing in the second half of 1967.

The 'Lamborghini Bertone Miura Roadster,' as it was officially christened, was finished in a light metallic blue with an off-white leather interior with red carpeting. The dashboard and steering remained black, and the steering wheel itself was the original avant-garde unit that was also used on the Marzal. This Miura carried chassis number 3498 (which, in accordance with its one-off prototype status, is not even listed in the factory's original production chassis number register), and P400 engine number 1642 was fitted.

For the January 1968 Salon de L'Automobile Bruxelles, Bertone pulled off another masterstroke when he unveiled this Miura Spyder to a gob-smacked Ferruccio Lamborghini, who, we are told, only saw the show car for the first time at the preview the day before. However, Bertone told Lamborghini to put any ideas of production right out of his mind: "We couldn't make this car for production because there were untold problems with stress-tolerance issues involving the chassis and the windscreen. It's purpose was simply that of a showcar," Bertone confided to a GM stylist years later.

With its Bertone publicity duties completed, the Spyder was sent to Sant'Agata, where it was famously photographed by both Zagari and Coltrin, and it was fettled by the service department with the idea of making it roadworthy to sell as an expensive one-off.

In 1968, International Lead and Zinc Research Organisation (ILZRO) CEO, the late Shrade Radtke, was looking for something radical to showcase the zinc alloys, coating and plating systems the company promoted for the major manufacturers in the Detroit area. It was decided to purchase a standard production Lamborghini Miura Berlinetta and have it specially built using zinc-based components and trim wherever possible.

Onwards then to Sant'Agata, and a meeting with Paolo Stanzani. However, Stanzani was against the idea of modifying a production Miura, and came up with the convenient solution of offering the one-off Miura Roadster, at the time at Sant'Agata for fettling. The offer was accepted on the spot.

In May of 1969, the "ZN75" was completed, now adorned with much extra brightwork and painted metalic green, and Bertone arranged for a private showing at a villa in Turin, attended by the hierachy of the Italian automotive industry. It was a special day, and Bertone, was proudly pictured with the car on that occasion.

There followed a globe-trotting schedule of International Motor Shows: August 1969 – Shown in Detroit, Michigan; October 1969 – Shown in Montreal, Canada; November 1969 – Shown in Anaheim, California; January 1970 – Shown in Detroit, Michigan; January 1970 – Shown in Montreal, Canada; February 1970 – Shown in London, England and featured on BBC TV; April 1970 – Shown in Palmerton, Pennsylvania; July 1970 – Shown in Tokyo, Japan; August 1970 – Shown in Sydney, Australia; and November 1970 – Shown in Paris, France.

After a final showing at the 1978 Detroit Motor Show, in February of 1981, Radtke donated the car to the Boston Museum of Transportation for an estimated $200,000 tax deduction. In the mid-1980s, it was refurbished and its interior upholstery replaced.

In 1989, it was purchased by the Portman group, and has spent its life since then shuttling from auction house to temporary owner, likely because its full history and significance is unknown by most. Auctioned off soon thereafter, it spent a number of years in Japanese collection. In 2002 it returned to the USA for a brief sojourn, before finding another home with a Ferrari collector in France.

In December 2006, the priceless Miura Roadster was finally purchased by a New York property developer who, at huge cost, has had the car returned to its original 1968 Salon de L'Automobile Bruxelles specification. The conversion, by the Bobileff Motorcar Company, was completed in late August 2008. The news comes from Joe Sackey, Miura expert and author of "The Lamborghini Miura Bible" to be published in November 2008 by Veloce Publishing Ltd.