Do these bolt directly to the factory fog holes, or do I need to drill?

They mount at factory points — no drilling. The bezel sits into the OEM opening. Test-fit before final fastening to confirm alignment.

The switch — does it tap into the existing wiring harness, or is it standalone?

Installation method and wiring requirements are not detailed in the specs. Consult your Tacoma service manual or have a shop verify the connection points before you start cutting into the dash.

Can I use these with a lift or leveling kit, or will the bumper angle affect them?

Suspension modifications don't change the fog light mounting points. Aim may shift slightly depending on how aggressive your setup is — plan on a minor beam adjustment after install if needed.