Just wrapped up my upgrade, disconnecting only the negative terminal... WOO-HOO!!! Absolutely everything works; okay the light for the Up/Down/Tune button is burnt out... but that's small potatoes! Only thing I have to do: sell the old parts on Ebay! Think $25 for the old clock spring (1/10th of brand-new price at GM), $25 for the steering wheel, or $40 for the whole shebang including sub-harness sounds reasonable?