After listening to all the advice and suggestions here, I decided to route the power cable through the back of the windshield, down through the slot at the bottom, between the headlight modules and then into the frunk where it can be attached via battery tender connector to the battery. This leaves it with power on always, but I don't intend to leave the gps sitting out there on the bike unattended anyway. This solution involved removing several pieces of tupperware to expose the space between the headlights, but that's it. I didn't have to cut any wires, tap into any circuits or drill any holes except for the small slot where the cable enters the frunk.
See attached pics (assuming I can figure out how to attach them)
View attachment 148549