Hate to be the party pooper, but as a an automotive lighting engineer (yes there is such a thing) there is no way placing red film over your STT lights maintains the proper, legal, and SAFE intensity for your stop lights. Your film also covers the side reflex area (shiny red side part) of your lights that are specifically designed to reflect incident light back to the source (the reflector part of the tail light, like a bike reflector).
There are very strict legal requirements for stop and turn intensities that I can guarantee you Nissan did not OVERSHOOT by the amount your film eats. The film over the reflex area completely changes the way it works and won't be legal as well.
While this does absolutely look nice you are creating a huge safety and legal liability for yourself. From a legal standpoint modifying your stop/turn/reflex lights to a level below legal limits is no different than disabling them. Imagine the field day any half-competent personal injury lawyer would have if someone was injured rear-ending you!