Drug Test Tomorrow!

Hey guys,

Sorry for another "will i pass" thread, but i'm really nervous about this test cause its for a job i will be holding for the rest of my life. first off, i'm about 6 ft 170 lbs with an above average metabolism. i havent smoked since 2/8/08, and given that my test is tomorrow, that will put me at 19 days clean at the time of the test. prior to that, i have been smoking 5-7 days a week for the last year and a half. i havent done anything to clean up other than not smoke and drink some cranberry juice everyday. i also bought 2 THC at home drug tests from walgreens last week, took both, and i think i passed. its hard to tell because i dont know how dark the line has to be in order for the test to be negative, even though the instructions say even a faint line for the test line is a negative (it has 2 lines, a control and a test). Tomorrow, i know i'll be taking an eCup test, and my question to you all is do you think passing the walgreens test is enough for me to just take the test, should i try diluting to be safe (will it show that i diluted it with an eCup?), or should i try subbing. Any help is greatly appreciated!