I did this a few years ago on my ITMs, and I have really liked the look. Since my ITMs are trash, I needed to route these things into the Nitto base bars. This can be done on any all-in-one bar that you desire to use Campy NON Ergopower levers on.

If no internal routing exists on your base bar, drill a hole about 10mm from where the aero bar will be mounted with an 8mm bit. Elongate the hole slightly. Make sure there are no bends anywhere near the hole.

Find where the cable exits, then scribe the mark 10mm from the end of the bar. Punch the mark, then with an 8mm bit, drill the hole.

After drilling the hole, use a Dremel tool with the cut-off wheels. Flare your hole from the top and cut from the end of the bar into the hole. This will need to be done twice with each hole. Use your grinding bit that is suitable for aluminum to smooth the hole. You now can mount the cable inside the bar.

The bar plug may need modification, which may require an 8mm hole near the edge of the plug. This insures that the cable clears the plug (and you will be able to race, since you will have bar end plugs). Then remove the prongs from the plug near the hole and directly across from it. Use tape or old bar wrap to make sure the plug is snug. Keep a couple of these modified plugs handy.