Drill the hole under your roof rack. Run the wire up the A pillar trim under the headliner to the hole. Put a grommet in the hole. Run the wire out the hole and to your lights.
Then, if you ever decide to remove the lights or the wiring for the lights, it is easy to patch up the hole and it is in a location you won't see the patch anyway.
Or, just mount the lightbar up there, drill your hole in your roof, leave the lightbar on if you sell it. It isn't hard to seal a hole where you run wire through. If you have nice lights on your lightbar, then buy some cheapies to put on it when you sell it or just raise your asking price so you can buy new ones.
AP9 - Go get some angle bracket material and attach it to the back of the frame where the bumper support attaches. Then bend a bracket to attach to that to hold your speaker on top in the position you want. You could also put it behind the grill by using some bracket material from the hardware store and attaching it to the header panel... it would be drilling a hole for a bolt, but it would be a hole in a place no one will ever see unless your front end comes off.