Reddit mentions of Replacement for Mazda 6 Driving Bumper Fog Light + Bezel Covers + Wiring + Switch (Chrome Trim Clear Lens) GJ1

Sure: My HIDs are actually the Kensun 35W 4300K kit, just because I wanted it to look stock-ish. Pretty happy with the result, kit was $50 and I bought a decent relay kit off of eBay for $10 or so. You can read up on how LEDs work with our housings, some say not to, others say it's fine with the right ones, but I'll leave that to your opinion.

So these are the DRL bezels themselves, you'll notice there's no fog lights in them. The same company also sells this set of bezels with only a chrome trim, but with the fogs. I ordered both (~$50 each pair) and swapped the fogs into the DRL bezels. Since I was adding fogs to a car without them, I also ordered the OEM turn signal lever/headlight/fog light switch. All 6's in this year range have the wiring for the fogs already down at the bezel, just not hooked up on cars not equipped with them. Other than an add-a-circuit for hooking up the DRLs, there's no other wiring needed.

For install, you'll need 2 hours or less. Mine took a little longer because I was trying to do as little work as possible (pro-tip: goes faster if you just do it fully).

Jack the car up and take both front wheels off (one at a time is fine if you can't) and remove the wheel well liner all the way down to where it meets the middle under-engine cover. The bezel covers (or fog bezels, if yours is already equipped with them) come out by pressing on 4 or 5 plastic clips, and they slide right out. The new bezels go back in the same way with a pretty good fit.

The OEM fog light plug goes onto your fog lights themselves (naturally), and the DRL connector will be connected to the harness that comes with the DRL bezels. Install both sides, then drop the wiring harness from the top of the engine bay down to the driver side, around the fuse box compartment. I also pulled down the under-engine cover and tucked the connection for the passenger side above it to keep it out of the way.

You can use an add-a-circuit in the fuse box on anything that will turn on and stay on when the car is running. If you use the original DRL circuit, the DRLs will turn off when your headlights come on. I used a multi-meter to test this, but from my reading some have put the add-a-circuit onto the audio or "MONITOR2" fuses. I chose MONITOR2 for ease of install and cleanliness.

That's really about all it takes, pretty painless and turns out pretty decent. They're not horribly bright and they add a little character. I put them in Friday, drove to the store Saturday and parked next to a '16 GT and the driver asked what trim level I had that got me the DRLs!