Will this work if my bumper has sensor holes?

This is an end molding cap—it covers the outer corner of the bumper assembly. If your truck has parking sensors, they'll be housed in the main bumper fascia, not in this molding. You won't have any clearance issues.

Do I need to paint this before installation?

Not required. Install it raw and paint after, or paint beforehand—your call. If you go raw first, just mask off any mounting hardware before spraying. Either way works fine.

How does this attach to the bumper?

Uses the factory mounting points on your Silverado's front bumper assembly. Standard bolts through the existing holes—no custom brackets or adhesive needed.