As far as getting the external cables out of the way for racks and stand clamps you can just release the brake and shifter cables by squeezing the pads together and pulling the cables out of the stops and shifting the derailleurs to the highest (front) and lowest (rear) and then without pedaling shift the levers all the way down which will also give you enough slack to remove the cables from the stops provided they are open to allow the cable to go through. As mentioned, besides the difficulty of getting the holes drilled properly, if even possible on your bike, for internal cabling the headache of changing out cables and possible rattling, etc., are just not worth it IMO.