How do you make high-quality mirrors that REALLY reflect the rear? That's what I'll teach you in less than 5 minutes!
I searched for weeks fiddling with my shaders and textures without ever getting a clean result on my mirrors, then I discovered this method, which is top-notch!
I'd like to point out that the point of origin on Zmodeler must be set correctly. behind (the side without the mirror) the rearview mirror and not in front of it or at its level, otherwise you'll never get a visual of the rear in it.
If you're not satisfied with the reflection, try moving the point of origin further away or closer to the mirror, but always without glue it!