Pastorbob...this from the Waterford website:
Starting in 1971, Schwinn outsourced excess Paramount production to Pioneer Manufacturing of Racine, Wisconsin, owned by Don Mainland. Don was an accomplished bike racer as well as successful industrialist. After racing in the midwest, he raced in Japan’s Kierin circuit in the early 50’s. He then returned to the US, where he set the coast to coast cross country record, which stood for eleven years. Don’s firm supplied the 1972 Olympic frames and Schwinn Superiors during the 1980’s. His tooling firm supplied Schwinn’s manufacturing all the way until 1990 in Mississippi.
During the 70’s, Paramount sales rose to 1,200 units annually. Schwinn supplemented Paramount production with contract-built frames by Don Mainland and Roger Nelson. Don and Roger, both riders from the 40’s and 50’s, had built up a successful tooling business in Racine, Wisconsin. He already supplied tooling to Schwinn. At Paramount’s peak in the mid-70’s, 10 frames per week came from Wisconsin and 15 from Chicago. There is no obvious way to distinguish the Wisconsin-built Paramounts from those built at the Schwinn factory. Serial numbers were issued after the bikes were built.
I seem to remember hearing that the Mainland frames had a P on the bottom bracket indicating Pioneer Manufacturing, but Waterford doesn't mention this.