Rooting the Cadillac Part 1: Lay of the Land

As a happy owner of an Equinox EV who has disabled all the Google apps and uses the giant infotainment screen as a glorified Bluetooth speaker and big trip meter, I am very interested in efforts to open it up to third-party software. I would love to have F-Droid and CoMaps installed on it, and even further some future LineageOS or postmarketOS build.