If IC has been named the primary beneficiary on your life insurance, go for it. We could use the money.
Seriously though, screwing with electricity when you've no idea what you're doing can get people killed. Don't do it.
There are 600W HPS to MH conversion bulbs, that's what you want for this application. It is a MH bulb made to plug into an HPS ballast (and is the only way to get a 600W MH).