I have removed loads of these, use a heat gun to warm the tint where you want to start then start peeling, use the heatgun( you must keep the gun moving ) whilst pulling the tint.
Sometimes the tint keeps braking, sometimes you can peel the whole lot in one go, depends on how long they have been on.
Once all the tint is off, use white spirit or a gum remover then use a window cleaner.