Debra I am not sure if anyone actually has a good answer for that question. I can tell you on my Bronco the wiring was there for the front fogs so all I needed was the switch and then Forscan to power them up. As for the back fog lights I'm not sure what Bronco would come with that setup, it...
This is what I bought for the factory harness, one wire will be hot when switched on and one will be ground.
https://www.bmotorsports.com/shop/product_info.php/products_id/4342
This is what I bought, when plugged in on each side one wire is hot and the other is ground, what you do with them from there is your personal preference.
https://www.bmotorsports.com/shop/product_info.php/products_id/4342
To my knowledge you are correct because no base models come with fog lights. The reason the other trim levels have the harness is because when you get the modular steel bumper you get an automatic fog light delete but the harness remains.
Yes, you can, all I would have to do is use one more wire and aux switch to do that. I just chose to isolate one as white for road use and both amber for offroad use. In Virginia you can only legally use 2 fog lights(one each side) at a time.
I hooked harness to right side and when I came over to left side I had to make several loops and zip tie it out of sight and then I could barely get wire up to top of engine bay for power.
I got mine in today and installed although I had a lot of trouble with the main wiring harness. The lights look great, the y connectors are great but the main harness is not correct.
Please check yours as mine has over 6 feet between the plugs that go to the y connectors and then only about 3...