I want to pull cable to my garage that I'm finishing so that I have power for outlets and wood working equipment. My breaker box is recessed on the exterior of my home with wood siding. There are plenty of knockouts in the bottom and I can add up to 4 new circuits to the panel (spare breakers). Are there standard approaches to cut a hole in the siding below the breaker box so that I can feed cable from EMT conduit? I can mount an all weather box with a 3/4" threaded hole in the back and connect conduit from there down to my garage. The question is, what's the best way to feed the wire from the weather proof box up inside the wall cavity to the knockout on the bottom of the breaker box? I'm considering metal flex conduit for the 6-8 " span. Are there better ways to do this?