Will these plug into my truck's existing fog light wiring?

Yes—the pre-wired connectors are designed to mate with factory Silverado fog light circuits. No rewiring needed if your truck came with stock fog lights or factory harnesses.

Do I need to use relays or a new switch?

LED projectors draw less current than halogen units, so your existing switch and factory wiring will handle them without modification. If your truck lacks a fog light switch, you'll need one added separately.

Can I aim or adjust the beam angle after installation?

Mounting method and adjustment points not specified—test-fit the assemblies at the bumper before final fastening to confirm beam alignment. Your service manual will show factory adjustment procedures for that location.