As some already stated, they did install it and Tesla Service was required to enable it. I looked on ebay and even Amazon (used), its about $100~200 for the part, and the wiring harness/mount is still in the car (cheaper to retrofit if Vision-Only didn't pan out).I would go back to the question, then, of can the radar unit be retrofitted, and would that cause the car to set itself to “radar=yes” or is more hacking required for the car to know that the radar module is there? Seems like acquiring a single radar unit not that hard and would increase the measure of safety substantially on my future Model Y