By 1967, Fiat was leading the European market, and its 50th anniversary was coming up. For the occasion, a new series was developed in Turin with more innovative characteristics than earlier models. The new series would be based on the Diamante series, and the name chosen was "Nastro d'Oro" or "Gold Ribbon", marking the "Golden Anniversary" of Fiat's "marriage to the land".

The appearance was a strong evolution of the Diamant series, again penned by Pinninfarina, with the longitudinal ribs of the engine cover now more predominant, and running though to the nose conferring lightness and movement. The colors were slightly changed as well, with a lighter orange for the bodypart, and blue for the mechanical parts, which gave the impression of a dynamic and modern machine. 

The new series wasn't only a styling exercise though. The series introduced new upgraded engines, all now with direct injection and rotary injection pumps, and all but the smallest reverting to a stressed crankcase design. Improved driving ergonomics, a number of new safety features including a lock preventing starting the engine while in gear, new 12 volt electrical system, upgraded gearboxes with synchronizers, and the control-matic three-point hitch now standard on all models, are just a few of the technical features to mention.

Some sources tell, that all models at launch had the option of a Frutteto, Vigneto and Granluce variant, though this has been difficult to confirm.

The first models of the "Nastro d'Oro series"/"Gold Ribbon series", were put into production in 1968.

The 350 had a lot in common with its smaller siblings 250 and 300, but also the larger 400 models, bridging the gap between the two, in terms of usabillty. For example, the 350 did use the 8025.02 engine from the 300, but with a stressed crankcase like on the larger 400 models, giving a more substantiel tractor with a higher loading capacity, though in terms of power about the same as the 300.

It was sold in Italy and internationally as the Fiat 350, but in France it was still sold as the Someca 350. Someca being the agricultural arm of Fiats French subsidiary Simca.

The gearbox was a six forward and two reverse, and had PTO and locking differential on the rear axle as standard. The model was also offered with draft control / "Control-Matic".

The 350 used the two cylinder watercooled, direct injected diesel engine from the 300, with a displacement of 1.727cc and stronger crankcase, developing 35 hp at 2.500 rpm.

The Gold Ribbon Series tractors enjoyed even greater success than its predecessor, being recognized for their new design, engines and features.
In 1968 alone, when the European market was contracting, Fiat produced a total of almost 60.000 tractors, 42.000 of which in Modena alone, 5.000 more than the previous year. That year also saw the production of the 500.000th Fiat tractor since 1918.