Will these plug into my truck's factory wiring?

Yes. These are designed to use the existing cab light mounts and wiring — just bolt them in place of the originals and you're done.

Do I need to do any prep work before installation?

Remove the old lights and clean the mounting surface if debris or oxidation is present. The black housings come ready to install with no painting or finishing needed.

What's the difference between LED and the stock lights?

LEDs are brighter, draw less current from your battery, and last much longer than factory halogen bulbs. They also match the look of newer trucks better than the original amber housings.