Hi I have done this install hidden light bar behind grill . If you get a good light bar they will supply plug and play wiring harness that has a switch for enabling the lights inside the car. and a wiring loom that connects to the headlight high beam connector behind your headlights . I got power supply by lifting up the positive jump start terminal under the hood and tucking the positive connector under the nut that holds the positive terminal for jump start. It looks very neat, then just unscrew negative jump start terminal next to this and place negative power lead under this, and screw back down.Done you now have power for you lights.
To get to back of headlight connector remove top of air filter box, very easy and this makes put headlight plug and play easy to install.
Then remove front grill, there are two upright supports for the radiator, I drilled two holes through these to mount the light bar. Positioned the light bar at the very bottom, sitting on top of the front bumper bar this seemed to let light bar line up with holes on grill.
I know it is not the perfect spot to fit light bar behind grill, but it does throw a lot of light, and you don,t know its there.
The bar is a 20" and just clears the grill if you fit it at the lower position because the grill slopes back as it goes up to the hood.
The grill takes about five mins to remove.
Figured it all out. Now the bar turns on when the highbeams go on (usually leave on auto). And I have a wireless switch as an over-ride. The bar itself is a BlackOak 30" Curved double row 5W LEDS. It fits nicely behind the grille so its stealth. The LED has is a dual Spot in the center and wide angle on the edges to create a HUGE about of light when on. Even tucked behind the grille it still is an insane amount of light!
Yeah, I don't have a physical switch wired thru the firewall either. I just use a FOB to turn the light on and off (for me when the high beams are on). One thing on my wireless switch is that when it is not getting constant power to the switch (the trigger wire), it always defaults to on (when it gets power). So when you wire it up with your relay, you need to feed power from the battery right to the wireless switch for the trigger wire, which then also means that you can turn the light on and off without the car actually being on....which I didn't like. Don't know if my wireless switch is stupid like that (defaults to on when it gets power from the trigger) or if you can get one that is different!!! Good luck!Nice. Would love to see some pics at night. I have a sport, but want to do the same thing. I'd be interested in the wireless aspect - I saw someone posting about a remote. I don't want to have the physical switch because that requires drilling and I wouldn't want to hook it to the brights. Thanks