As you know, HUD technology is all about how the effect light reflection does and does not work with the front windshield. I would never try to tint my front windshield as most are illegal in every state I've lived, but if I did.... I'd get an installer I planned to use to give me a large enough scrap piece that I could first apply temporarily in the area of the HUD display, and try that in every sort of lightning condition I could -- night, day, full on sun in your face, sun towards your tail end, etc, and then do the same things with polarized and non-polarized sun glasses to be sure I understood the effect and if was acceptable to me. Good luck with what you do.
Present: Tesla S90D
Past: '13 RX450h; '14 MBZ SLK250; '06 RX400h; '09 BMW 335i; '02 SC430; '99 RX300; '95 SC300... and a few before that.
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