If it was me, and I didn't want to drill into the bumper, I'd get a light bar that had mounting dimensions similar to the mounting points for the winch fairlead, and either :
1) Modify the lightbar mount to bolt on at the fairlead mounting points
or
2) make a flat plate that the light bar mount mounts to, and then mount that plate to the fairlead mounting points.
Honestly, I can't see me ever mounting a light bar an any of my vehicles (altho I do like the one Quadratec sells that has the clearance marker lights made into it for once the lift is done), but it's not rocket science, nor hard to do. I personally would just drill holes in the vertical face of the bumper where the fairlead mounts, maybe install some appropriately sized nutserts if the backside of the holes are inaccessible, and bolt the light bar/mount on that way, but I understand somewhat not wanting to drill into the new bumper.
I'm sort of in the same boat, as the front bumper I want to install comes with a fairlead mounting plate welded on, but the odds of me actually mounting a winch on the bumper is about 1 in 100, as I want the winch mounting surface more as a place to stand or kneel when working on/in the engine compartment (short legs and a hefty mid-section).
I have explained this to the bumper manufacturer, and even when hinting that it could cost them the sale, they refuse to send me one without the plate welded on, so I will have no choice but to cut it off and repaint/recoat the bumper if I am gonna use the winch mounting surface as a place to kneel on when working under the hood.
The cutting it off and welding it back on at a later point isn't the deal, but I wanted to keep the factory paint job on it.
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