Drivers side. there are 2 big water drain holes in the bottom front of the cage. I used a 3/8" drill bit & drilled from the water drain hole at the front upper cross bar(roof) into the left A pillar of the cage. I also am running a heavier gauge wire than you probably need if you are running a led light bar. I'm running 5 hids up top so I went with 12ga wire.
make it easy , what ever side your wire is coming out run in down , my wire is in center but ran it down the passenger side, feed it thru the side panel drilled a hole behind the removable piece and behind the center dash is a plug to wire it right in !
I see the drain hole in the horizontal top bar. Are you saying that there is one on the verticle drivers side. Is there another one under the plastic cover that covers up the small bar that is on the the top of the verticle bar the one that has three little rivet looking pins in it? Or down low where it mounts to the frame? Just a little confused where the second drain hole is.
On the top horizontal bar, drill from the water drain hole into the vertical bar. At the bottom of the vertical bar were it bolts to the body there will be 2 drain holes about 5/16-3/8". You will need to unbolt the cage to lift it up to access these holes. You can then fish mechanics/bailing wire through one of the lower holes then up to the hole you drilled at the corner of the upper horizontal bar & vertical bar. Tie the wires you want to pull through to the mechanics wire or whatever you use then pull the wiring through the cage. Everyone has their own methods but you will want to make sure your positive wire has protection from possibly rubbing through or pinching in the cage. I put a medium wall heat shrink over my power lead then pull the wiring through the cage then put a heavy wall heat shrink over both wires(power&ground) where it goes throught the holes drilled in the cage.