I have the Garmin Dash 46 mounted right below the frit in the top center of the windshield. I route the wire up in the space above the headline then shove it into the space between the windshield and A-Pillar, then through the dash and A-Pillar, and down the door and under the glove box.
I have heard of people using this: https://www.amazon.com/dp/B08FQ7C9B8?ref=ppx_pop_mob_ap_share
To use the power straight from the rearview mirror and it working fine.