they all came with the 3k. the 4k is "deeper" than the 3k and will hit the grill, I think they are the same in proportion otherwise? I think it depends on which mount you have I think some brush bar set ups needed a mount, some brush bars had the mount integrated but I am not sure. It is possible to cut the grill or make up something simple to mount the light on that would move it out from the grill. good luck...
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