Will this cover my factory fog light cutouts, or will I need to cut new holes?

The M-1 design maintains the stock fog light opening locations, so your existing wiring and housings work without modification. If you run aftermarket fogs with different sizing, you'll need to measure and cut accordingly before painting.

Does the lower valance interfere with parking sensors or bumper-mounted hardware?

The M-1 drops lower than stock, so if your car has rear sensors, PDC wiring, or other hardware mounted to the bumper beam, verify clearance before final fitment. Most bolt-on sensors and connectors sit far enough back, but measure from your current bumper to the bumper beam just to be safe.

What's the best approach to paint this before installation?

Primer is already applied and sealed, so you can spray base and clear coat while the bumper is on sawhorses in a well-ventilated space. Mask off the mounting tabs and any areas that will contact the car body. Once fully cured (follow your paint's cure time), bolt it on—no additional sealer needed at mounting points unless you want extra protection against moisture.