For your SBC-ID, where did you tap power from? I tapped from the radio and never had any issues. For illumination, you should be tapping the orange/white wire IIRC.
For your friend's HU, the reason why nothing saves is that you tapped the ACC wire which only provides +12V when the key is in the ACC or ON position. When you turn the ignition off, the HU loses power and it's memory is lost. You need to tap a constant +12V source. Should be a blue/red wire IIRC. . .you can just use a multimeter and test the wire to find a constant +12V with the ignition off.
Here's a link for a '02 wire harness from the radio: http://www.northursalia.com/m.../radiowrx.html