U.S. oil supply worries found fresh impetus on Tuesday after the American Petroleum Institute said that both crude oil and product stocks had fallen again -- hard on the heels of a massive draw earlier this month. U.S. crude stocks are now at their lowest level since March 1976. Crude oil prices were up sharply in after-hours trading after a decidedly bullish API report showed a 2.1 draw for the week ended August 4, despite a rebound in crude oil imports, which rose 1.34 million barrels to 9.36 million bpd. Compared with this week a year ago, crude stocks are down 40.4 million barrels. The API also showed that U.S. distillate stocks were down 1.2 million barrels on the week (down 27.7 million barrels from this week last year)…