Ya, for window tint to settle correctly, sunlight is a plus. Not sunlight creeping through the 30f winter sky, but through good spring/summer skies. Think of the old Shrinky-Dinks.... it works much the same. It needs to be "baked" so to speak. Evaporation needs to take effect and it also helps the adhesive catalyst take effect.

I would love to tint my windows again, but state and county police have already had me pull my tint twice. The second time, it was completely legal, but they didnt see it that way. I will NEVER tint my vehicles again. I have actually gotten used to sitting in a completely visible bubble, heh. If anything, I get less attention now without tint. A welcome change.