obijohn has a good idea, don't forget a final flush with pure water. This working will really depend on your weight believe it or not, your 6' 150lbs its gonna go a lot better than if you are 5' 300 lbs. They do have commercial flushes available, may consider that route as this would be a really bad one to fail. Although in many cases dilluted piss is a fail and they all (i believe) work on a flush and dilute theory, the exact same as the cranberry water idea. If you go the cranberry route, don't forget about cranberry sauce, really high cranberry content, and you can eat it not just have to drink it. Wash it down with cranberry juice for the week everytime you possibly can. Then spend 3 days flushing with pure water. Good Luck.