I have a Saliva (Swab) test tomorrow..any advice?

Okay, so I have a saliva swab test tomorrow (Tuesday, 10/22) at 6 o'clock in the afternoon. It's for a job at Kroger supermarket. I'm a big guy, 6 ft tall, 270 lbs. and i've been a heavy smoker until recently due to a drought where I live. from Tuesday up until Saturday (10/19), I've only smoked a GB or two a day. I know that the detection time is rather short, but here are the steps I have taken to prepare for the swab test. any suggestions to further prepare are wanted and welcome! also, please tell me if i'm screwed or not.

-Smoked twice Saturday night, consisting of 3 GBs in total. mouth washed after each one, and brushed my teeth
-stopped smoking after Saturday night, around 8:00, haven't smoked since
-brushing teeth 3 times a day since, using mouthwash before
-started drinking a gallon of water today

Tomorrow right before the test, I plan to:
-drink 2 gallons of water in the hours leading to the test
-mouth wash and clean my mouth thoroughly at least 5 times before the test
-eat supper 45 minutes before the test
-in the parking lot before the test, I plan to wash my mouth out again with mouth wash and rinse with water.

I know it's a good idea to avoid contact with your tongue and cheeks when you put the mouth swab in, but how can I do it without them noticing? put it in between my back teeth or what?

so am I good or what? 70 hours without smoking and above steps. What else should I do, and what is my likelihood of passing? I really need this job. being broke isn't fun, and jobs don't come around often where I live.

okay, so i took the test today, and here's what I did.
1. Brushed 4 times prior, using mouthwash after each time. The mouthwash I'm using is whitening, so it has hydrogen peroxide in it.
2. 35 minutes before the test, i ate a chicken sandwich and washed it down with coca cola, saving some for later.
3. on my way, I popped 6 ice breakers, letting them dissolve in my mouth.
4. When I was in the parking lot, I mouth washed again, and then I swished some cola in my mouth.
5. waited 10 minutes till the HR rep came to get me for the test, in that time period i popped one more mint.

I got to the test, then I had to fill out some paper work, another 15 minutes. '
After that, I took the test. when she told me to take the test, she told me to hold it to one of my outer mouth walls, which i didn't. I held it in the opposite way against my teeth. 5 minutes went by, and the test had a blue indicator on it. it had barely moved. After that, I kinda rubbed it against my teeth until it turned blue. I think I may have fucked up there. I don't know. Did I?

I've been employed for Kroger for almost two years, when I took my test it took fooorreever to finish the test. Idk why, but I ended up passing. I didnt smoke much then, but those tests are only good for 48 hrs at most. With all that washing and 70 hrs I think you'll be good