Original sentence: American Motors lter began the process of differentiating the Rambler brand name from its various sizes and similar model names.However, this model became the replacement for the large-sized Nash and Hudson models that suffered from dwindling sales.In 1956, the four-door Rambler models were completely redesigned and the short-wheelbase two-door versions were dropped.In 1957, the Rambler was established as a separate marque and these models became the foundation for the company's best sales through the late 1950s.The Rambler Six is an intermediate sized automobile that was built and sold by American Motors Corporation (AMC).The Rambler was sold under the Nash and Hudson brand names.The new line retained the  wheelbase, but the overall length was increased
Edited sentence: American Motors later began the process of differentiating the Rambler brand name from its various sizes and similar model names.In 1956 Rambler was sold under both the Nash and Hudson brand names (the merged companies forming AMC in 1954).In 1957, the Rambler was established as a separate marque and these models became the foundation for the new company's best sales performance through the late 1950s.The 1956 four-door Rambler models were completely redesigned and the short-wheelbase two-door (Nash Rambler) versions were dropped.The Rambler Six is an intermediate sized automobile that was built and marketed by American Motors Corporation (AMC) from 1956 to 1960.The new line retained the  wheelbase that was used for the previous four-door versions of the Nash Rambler, but the overall length was increased.This model became the replacement for the large-sized Nash and Hudson models that suffered from dwindling sales