To get to the CD changer: take a cloth-covered flathead screwdriver and pry the clock towards you from the right side, then two screws are visible. Unscrew those and more of the trim comes off; unclip the power socket's connector and then twist that trim out of the way, and then there are four screws for the stereo cluster, then four screws for the CD changer itself once the stereo cluster is pulled out. In fact, here are some pictures I took of the dashboard disassembly to get to the stereo cluster (click to enlarge):
I don't know how to fix the error 2 code. I ripped up my 6CD changer to retrieve three stuck CDs, then junked the unit. It was pretty heavy in weight.
I know somebody on eBay fixes these 6CD changer units and corrects the inherent flaws to hopefully prevent common issues from happening in the future. Perhaps you should go this route if you wish to retain the stock system.
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