OP: By ignition switched wire they mean a wire that only has power when the car is on. This is the wire that allows your radio to turn off when you turn the car off. You need another wire that has a constant 12V regardless of the car's condition (on or off) so when the car IS off, the radio doesn't lose all power and reset to factory default. If you can't find one or both of these in your dash you can tap into fuses to get the right signals. As stated before you can use the wiper fuse, or anything else that is only powered when the car is on. If your not sure, grab a digital multimeter ($5 at walmart) and check which fuses are live all the time and which are only live when the car is on.
Why would he need to dig into the steering column? That's just adding extra work.