Do I need to modify any wiring to install the switch?

The switch comes with a pre-terminated connector designed to plug into the factory harness location. You'll route it to the dash and mount it in the stock position—no splicing or rewiring required.

Will this fit if I still have the OEM fog lights in place?

These are designed to replace your current fog assembly. If you want to keep your original lights, you'll need to remove them first. The bezel and mounting points are matched to the factory opening.

Are the lenses sealed against moisture?

The housing is built as a sealed unit. If you live in a wet climate or plan to track the car, inspect the seals during installation to confirm they're seated properly—moisture inside the lens will fog it over time.