Yea the biggest things with these spray on chrome finishes is prep, patients and a clean spraying area.
Also, when you lay down that primer or base coat black make sure you get an even nice coat. Dont go to heavy or that orange peel with show up in your finished product too. The basic problem alot of guys have with this is patients. People think they need to add more paint to get the effect so they hammer it on... Well all it does is turn something that would look close to mirror finish into metallic silver finish.
Yea the box is just a simple way to keep everything clean. One tiny dust nub will reflect in the finished product..
Never heard of anyone not clearing the finished piece ? Thats new to me, Im still not sure how it doesnt cause drama with the mirror finish even though it eats into the other base coat...... Im curious to see how it holds up