For major coachbuilders was a common practice to have sub-suppliers making part of the production.
Maggiora has been until the early 2000s one of the biggest. This firm has been established in 1925 by Arturo Maggiora as a "martelleria" (it means a workshop where artisans form the metal-sheets with a hammer).
Maggiora was specialized, in fact, in making the body-in-white and then its customers painted and mounted the rest of the vehicle.
Its relashionship with Viotti dates back to the origins, and Maggiora supported it for half a century.
The firm also made the body of a lot of other cars, like the Grand-Prix for Francis Lombardi, the Alfa Romeo 2000 and Lancia Flaminia for Touring, the Mangusta and Pantera for De Tomaso.
In the last years it made the Lancia Delta Evoluzione and the Fiat Barchetta (this time, the complete production, starting from the rolling-chassis received from Fiat) and several conversions of LCV for mail deilvery and public servieces.
It closed in 2003.
In this picture, it's difficlult to position Monterosa: customer of Maggiora (with something similar to the Giardinetta Viotti) or sub-supplier of Viotti in competition with Maggiora. I'd say the first, but again no evidence and just personal feeling.
