Here to report back that the installation of the mirror was a success. It was straightforward, there was no need to remove the plastic cover that surrounds the mirror nor did I need to remove the panel covering the pillar.
Hats-off to Rav4Gen5's excellent Dash Cam installation video
HERE, which was a huge help on which panels to remove, how to easily hide the wire run and connect them to the fuse box and ground.
The only difference from the dash cam application is that you will need a constant power feed in addition to the ignition power feed. To make things easy, there are two available slots in the fuse box. The one shown in Rav4Gen5's video is for the ignition power feed, the other is for the constant power. The wire diagram below provided by watchmanic (thank you!) was very helpful as this was not included with my installation kit.
The kit contains everything you need to install the mirror. Included in the box is the wire harness, wire ties and six plier tap connectors that fit seamlessly with the power feed end of the harness cable. I chose not to go down the plier tap route and instead opted to use an add-a-circuit kit to plug directly into the fuse box.
Gentex ADVGENADLN Frameless Auto-Dimming Rearview Mirror HomeLink
Littelfuse Holder Low Profile Mini Add-A-Circuit 10A Card (includes an assortment of 4 fuses)
1. Remove the old mirror with a torx screwdriver without removing the surround.
2. Feed the harness cable through the hole; power connection end first.
3. Pull the cable all the way through, re-attach the mirror to the windshield, connect the mirror's cable to the harness; hide the remaining cable inside the surround.
4. Continue along the ceiling, tucking the cable inside. Use a plastic trim removal tool to gently pry open the tight areas.
5. Continue across and down the pillar to the fuse box area, connect the ground & ignition power feed as seen in Rav4Gen5's video.
6. Connect the constant power feed to the only other open slot in the fusebox.
7. Enjoy your new mirror!