By November 1955, it was decided to "re-vamp" the Metropolitan, and it was now fitted with a 1500cc "B" series engine of 52bhp, and sported a "two-tone" paint finish with the colors seperated with a Stainless steel "Z" moulding. New colors of Carribean Green, Sunburst Yellow and Coral Red were introduced with Snowberry White as a contrast. All convertibles were fitted with black tops. The non-functioning hood "air-scoop" was deleted to give a cleaner line, and new upholstery installed. The new model was launched on 9th April 1956, and was now called "The Metropolitan 1500" with no Nash or Hudson name. By April 1957, new colors were released with Sunburst Yellow, Berkshire Green & Mardi-Gras Red being offered with Frost White as a contrast. The model continued with very little change apart from the engine being changed from a low compression of 7.2:1 to a higher 8.3:1 which gave a lift in power to 55bhp. Also in January 1958 the color Sunburst Yellow was replaced by Autumn Yellow, and Classic Black was added.
In October 1956, Austin Motors secured the rights to market the Metropolitan in the UK and other markets not served by American Motors. In April 1957, the Metropolitan was released on the UK market in Right-Hand drive configuration. It was also sold in other countries including France, Germany,Swizerland, Holland & South Africa. Although sold by Austin, it never carried any external Austin badging, and was just referred to as the "Metropolitan".