Had my cars tinted here an there for years.
Every state is different.
When I need tinting I do the research and find out what's legal .. no muss no fuss.
true, funny story:
Useda race my lil '62 Nova wagon in NHRA brackets ..same track, same inspectors, for a year or so.
Workin at a speed shop part time, I got a lotta decals.. my tool box got full so I started stickin 'em on the back side windows.
One fine day, the tech inspector says I had to remove them from the back side windows, as it blocked the drivers vision.
Well.
I had the back doors welded shut, took out the back side windows, put in aluminum sheet panels, did a bit of body work,
..voila!
Sedan Delivery instead of Station Wagon.
Completely legal.. and we both laughed about it at the next race.
(and the car was lighter and faster ..had no idea those windows were so heavy)
-GE aka Frank