Do these mount using factory mounting holes?

Yes — these mirrors use your vehicle's original attachment points with no drilling or bracket modification needed.

Will the heated function work if I don't have towing mirrors on my truck now?

These are a direct replacement for factory mirror locations. If your truck has mirrors, these will bolt in place; verify your specific mirror configuration before ordering.

What do I need to connect the heating and LED signals?

Wiring harness and connection method are not specified — have an installer verify compatibility with your truck's electrical system before purchase.