Do these plug directly into my factory harness or will I need additional wiring?

These are designed as direct replacements at factory mounting points. Exact wiring compatibility depends on your vehicle's factory electrical setup — test-fit the connections before finalizing installation to confirm proper fitment with your harness.

Are the LED bulbs replaceable if one fails down the road?

The LED units are integrated into the complete assembly. If a bulb fails, the entire fog light unit will need replacement — they're not separately serviceable.

Will I need to adjust anything after installation or can I just plug them in?

Once mounted at the factory points, these should align with your original fog light aim. If you notice the beam pattern needs fine-tuning after install, most fog lights have minor adjustment points — check your assembly for any vertical or horizontal adjustment screws.