I hate to affect this conversation but , the starter drive splines on the armature are designed for the motor rotation as well as the sprag in the starter drive . You can get the starter to rotate in the opposite direction but , you can't fix this problem .
I went to a buddy's house a few years ago where he replaced the battery on his Dixie Chopper . He replaced the battery and the starter would no longer engage .After an hour of work , I found the battery installed backward . The most important "moral of the story" . A permanent magnet motor will rotate backward when you install the battery backwards .