I have been a long time meditator, so that has helped me a lot when it comes to mitigating these hardwired responses. But it was not just the meditation, but also the physiological knowledge of how and why it happens. Having an understanding of both, it allowed me to apply my intellect in a more precise way so that when the emotions do arise, I was able to not only understand them, but breathe my way through them.
For me, the way has never been around, but through. Usually the emotions has a lot associated with it too, past memories, family, cultural, personal and emotional conditioning. I've found that as I traded, i've had to deal with a lot of stuff that came up for me personally. Not just about money, but about my own sense of personal worth. Needless to say, it was and is a deep and powerful subject. It takes a lot of energy to deal with it and it is more than just "being disciplined".
I've found that the one key thing for me was to have a keen sense of self awareness and the emotional intelligence to deal with my personal conditionings. This has been the most powerful tool for me.
Godo luck to you.