Metro’s old 1000-series rail cars will eventually be replaced by new 7000-series cars. Photo by ep_jhu Almost a year after the National Transportation Safety Board scolded WMATA for failing to heed advice to remove its oldest rail cars from service, the transit agency’s board has voted unanimously to approve the purchase of brand new replacement cars. The new cars, commonly known as the 7000-series, will be manufactured by Kawasaki Rail Car, Inc. at a…