Will this mirror mount at the factory attachment points without drilling?

Yes. This mirror uses the existing factory mounting holes on the door—no drilling or welding needed. Bolt it in place using OEM fasteners.

How does the heated element work, and do I need to wire it myself?

The heating element plugs into the factory harness on your truck. If your Super Duty already has heated mirror wiring routed to the right side, connection is plug-and-play. If not, you'll need to run the wiring from the cabin switch to the mirror—routing detail depends on your specific truck configuration.

Does the mirror stay stable at highway speeds?

Factory-style mirrors are engineered for OEM duty cycle and speed ratings. Stability depends on proper installation at all mounting points and correct adjustment angle—do not over-torque fasteners.