Complex sentence: In 1915, they won a contract to use the panels as automobile tops and for the next 10 years they supplied board for the tops of Ford, Buick, Nash, Studebaker, and Dodge.
Split into simpler sentences: In 1915, the company won a contract to use the panels as automobile tops. From 1915 to 1925 they supplied board for the tops of Ford Motor Company, Buick, Nash Motors, Studebaker, and Dodge.