Will these lights work on a stock bumper or do I need an aftermarket bumper?

These fit the factory bumper side marker locations — no bumper swap required. They plug directly into the OEM harness.

Does the crystal smoke affect how bright the lights are?

The smoked lens reduces output slightly compared to clear, but they're still DOT-legal and visible during day and night. If you need maximum brightness, clear lenses are the move.

Are there any sensor holes or harness adapters I need to know about?

These are direct plug-and-play into the factory side marker positions. If your bumper has been modified or has extra cutouts, test-fit first to confirm they line up with your specific setup.