I usually run them through the hole in the bracket, under the hinge, and then under the cowl into the engine bay through a hole with grommet.
(by the way....skip the Rugged Ridge mounts. The holes don't line up. I use the KC brackets with no issues)
Here is a bad pic of where the wires come out under the cowl when they come out from under the hinge. You can either extend the ground wires to one ground point, or you can ground them right there.