The year was 1952, and a slump in the Italian coach building industry was the direct cause for the design and eventual production of the Arnolt-M.G.

Considered by many people to be the most attractive of the custom bodied cars based on the M.G. TD; it would have been built if FIAT had not changed car production over unit-body construction. This eliminated the major source of chassis frames used by almost all the coach builders that Italy has been famous for. One of these was Bertone, which survives to this day, largely because of the Arnolt-M.G.

Since Bertone had almost no work, apart from SIATA, who supplied their own chassis, Nuccio Bertone, the son of the company's founder, looked around for a foreign chassis and located a pair of used M.G. TD frames. These were probably from accident damaged cars left behind by tourists. On these the company constructed a coupe and a convertible, built "on spec", in the hopes of finding a buyer for them. The whole process was very much like the building of a kit car today, which starts with a VW or other chassis. Both cars were completed in time for the Turin Auto Show in April of 1952. It was at the show that the fateful meeting between S.H. (Wacky) Arnolt and Nuccio Bertone took place.

Wacky Arnolt was an American industrialist who, among other things, was the midwest distributor for BMC. He attended the show to look for other makes to add to the automotive side of his empire, and came upon Mr Bertone and his two M.Gs. Bertone was nervously scanning the crowd, hoping to find a buyer for at least one of the cars, when up came Wacky. The reason for the nickname is another story, best left untold. He was wearing a white cowboy hat, high heeled boots, and allowed as to how he liked the cars well enough to buy 'em. "You mean you want to buy both of them?" Bertone is said to have stammered. "I'll take a hundred of each, if you can build them" Arnolt replied. Wacky said not to worry about the frames, since he figured he had enough influence at the M.G. factory to get whatever he wanted. The deal was made, and the two "prototypes" were shipped to the US and made their first public appearance at the races at Elkhart Lake, Wisconsin in September of 1952. These two early cars, which did not carry Arnolt badges, are slightly, but visibly different from the production cars. The whereabouts of neither of them is known at this time.

By the time of the International Motor Show in New York City in April 1953, cars with badges and the altered crease lines on the doors were shown. They carried a price tag of $3145 with disc wheels and proved popular enough so that several were sold immediately. Sales soon slowed however, and the last cars weren't sold until 1956. Final production numbers were: 65 coupes and 35 convertibles. Whether these numbers included the two prototypes is not clear. There is at least two possible reasons why the total order was not built: A). The cars were all built on the TD chassis, and the TF chassis (which commenced production in October 1953) was not made available. B). With the addition of a few options, the price was about the same as the base price of a Jaguar XK 120. It is probable that both of these reasons combined to cut production short. In any case, the Arnolt-MG was still the most successful of the M.G. TD and Y based coach built variants by a wide numerical margin.