I'm an aircraft engineer in real life, and electrics are becoming a HUGE part of everyday life now! I must say I am in agreement with Tabetha! An alternator, due to the internal windings will work if turned in either direction - any pulley nut, whether running CW or ACW, provided it is secured tightly should not come loose - think about wheel nuts - your drivers side wheel turns CW in relation to yuor wheel nut threads - and the passenger side turns ACW in relation to the nut thread - but your wheels dont come off on a long journey!!