The difference between honor and enlightened self interest is simply this: If placed in a scenario where you had to choose between your wellbeing and following your honor code, enlightened self interest says to act to preserve your wellbeing. Many people who consider themselves honorable, honest people merely have codes that almost strictly adhere to enlightened self interest. But there is always some thing they espouse that varies. Mainly to prove that they are not selfish, contradictorily. And when that point is reached, what decision they make is the one that defines them. Anyone can be good, can be honorable when it is easy, when their code is not tested, when they are not impacted. But to act against your self interest to adhere to a larger ideal, that is the definitive action that echoes forward.