I haven't paid attention recently but I always thought the side view mirrors didn't dim. My rear view mirror does for sure but I'm not sure about the side. I have 35% all around. Have to pay attention tonight and see.

 

My side mirrors do dim. I tested the dimming by covering the sensor in back of the interior mirror with my hand. After a few seconds the side ones look tinted too.

 

There are two light sensors in the interior mirror. The one on the back side of the interior mirror that you covered is the ambient light sensor. The glare sensor is on the front side behind the mirror glass which is why back window tint messes up the auto dimming when vehicles are following behind at night.

The video at the following shows these two sensors: https://jalopnik.com/the-way-auto-di...lly-1796939685

 

Professional tint shops use a steamer to remove tint film, especially on rear windows with defrost wires.

You might be able to rent a steamer, or buy a cheap steamer, to do the job. Just take your time and let the steam do the job of thoroughly loosening the adhesive before using any significant force to pull the tint off the window. The tint should almost fall off the window like wet newspaper when using a steamer.