You’re doing it all wrong. Both bottles are connected behind the front seats on the floor. I’ve had both my NOS bottles connected for a year and my car will be appearing on Street Outlaws later this year.
You combine it with some diesel, stick it in a rocket combustion chamber, point the nozzle backwards, and tada! 0-60 in 1s. At least once. Oh, don't forget to mount the combustion chamber well, or some parts of your car will be crossing the finish line a lot sooner than others.