I know its all I ever say in these kinds of threads, but I would recommend substitution in your case.

Its a surefire way for you to pass the piss test, irregardless of your current or past use. I couldnt tell you how long it would take for you to get everything out of your system normally, but I can tell you for around $30 you can walk in tommorow and pass if you do everything properly.

FBR will likely be back with more informative information shortly, but IMO, a bottle of QuickFix would solve the entire problem.