Will the heating element work with my factory wiring?

This is a direct OE replacement, so it's designed to plug into the existing heated mirror circuit. Check that your vehicle has the factory heated mirror option equipped before ordering.

Do I need any special tools or adhesive to install this?

Installation method varies depending on your mirror housing design. Some lenses pop out and in; others may require gentle prying. Test-fit before committing to any adhesive or fasteners. Your service manual will show the exact procedure for your vehicle.

Is this the full mirror assembly or just the glass?

This is the glass lens only. You're replacing the transparent part; the mirror housing and mounting bracket stay on your vehicle. If your mirror motor or housing is damaged, you'll need the full assembly instead.