Do these require any wiring modifications to the car's electrical system?

The harness connects directly to factory wiring points behind the bumper and dash. You'll need to identify the factory fog light circuit or run power from the battery; no modifications to existing circuits are necessary if factory fog locations are still present.

Will I need to remove the front bumper to install these?

Yes. Access to the mounting points and wiring routes behind the bumper requires removal. Plan for basic hand tools and roughly 1-2 hours of work, depending on your comfort level with panel removal.

Are the bulbs replaceable, or do I have to buy new housings when they burn out?

H11 bulbs are a standard automotive bulb type and can be swapped out without removing the housing. Replacements are inexpensive and widely available.