Auto-Dimming Rear-view Mirror Override (Electrochromic)

I drive a 2013 Subaru with an automatic dimming mirror. Most of the time it's great, but there have been a number of instances where I want it to dim but it just won't. There's no manual over-ride. This usually happens at dawn or dusk.

That's what drove the creation of this little add-on device. When you close the slider it blocks the ambient light from the sky, and the mirror thinks it's night. Using 3M trim tape (available at auto supply and hardware stores) you attach this device to t