Do these use the factory bolt-in locations?

Yes. These mount at factory rocker points with no drilling or custom fabrication required. You'll need basic hand tools and access to the mounting area behind the bumper.

Will the LED halos stay on all the time, or can I control them separately?

The halos illuminate independently of your low and high beams, so they'll remain on whenever you have your headlights activated. If you want them off, you'll need to cut power to the circuit—toggle control is not built in.

Do I need to reprogram anything or splice into existing wiring?

The projector lenses plug directly into your factory headlight connectors. The LED halos require a separate power source and ground—you'll need to run wiring to a switched 12V source and chassis ground. No reprogramming needed.