Do I need new wiring to install this, or does it plug into the existing harness?

This mirror uses factory mounting points and integrates with the existing electrical connector. Confirm your vehicle's wiring matches before finalizing purchase — older vehicles may have different harness configurations.

Will this mirror fit the left side, or is it right-only?

This is a right-side unit. Order the corresponding left-side mirror if you need to replace both sides.

What's the return window if the mirror doesn't work when installed?

Check the return policy at checkout. Test the mirror's power adjustment before tightening all fasteners so you can catch any electrical issues before full installation.