So I have run a switch for the electric fan into the cabin and my wiring harness for 2 little spotlights that I mounted to the front bumper will be in tomorrow. The fan switch wiring I ran through the same grommet that the hood latch cable runs into through the firewall. I myself am not a fan of this choice and with this new wiring harness coming tomorrow, what firewall hole do you guys use to make clean and well hidden wiring jobs?

 

Ive always just used the stock firewall hole the wiring harness runs through. I attached wires to the end of a straightened coat hanger and pulled them through. Just how I did it.

 

I drilled a 1/2 inch hole right next to the factory harness and installed a grommet and ran my wires through there.

 

I put factory fogs in an '00 XJ that did not come with them. Just the wiring in the engine compartment is not factory. If you look in the engine compartment you will see a bunch of wires coming through the fire wall below the Power Brake Booster. Above it is a disc of some sorts. Can also see all this from up under the dash. Decided to come through there. Using a 1/2" drill bit, plenty of room to get a drill in there from inside the engine compartment, I made a hole. Rat tail filed it a little more to get a grommet to fit in there. Those grommets are big enough to push the loom through. I used a dab of RTV inside and out just to seal it up a bit.
Used 1/4" Split Loom from Napa NW 737299 and these Rubber Grommets NW 784632.