no need to drill any holes, there is a rubber gromit roughly at the bottom of the glove box that can take the power cable.
To run the cable to the boot, my personal preference is to take the passenger seat out and run the rca's down the centre of the car and the power cable down the passenger side door.
You can run it from the side of the car. Left of the seat, behind the plastic panel, under the carpet next the sill, behind the plastic panel thing next to the accelerator (or other side) and to the Head Unit.