This page probably also applies to Monte Carlos, Grand Prixs, and possibly other GM vehicles.
(I do not recommend this mounting location - the bolts for the brackets are actually on the outside of the car, where water runs off the rear window and trunk.)
I recently purchased an SSI America NeoChanger CD changer (10 disc) from Best Buy for use in my Impala. I don't recommend the changer, especially for the Impala and similar vehicles. Here's why:
Although the sticker on the unit says it'll work for a 2004 Impala, it's not as simple as it is for every other car. Why? There aren't any adaptors for the 2004 Impala included, and none exist. You have to splice into the wires behind the stereo, a fact conveniently not mentioned when you buy it.
I found this out by calling SSI America (one thing about them is that they answer the tech support phone quickly). The person I spoke to immediately understood what I was talking about and e-mailed me directions for the installation. The directions they sent me made it seem fairly easy, so I broke out the soldering iron, ripped apart my dash, and plunged in.
Problem #1: I needed to extract (i.e., reuse) two of the pins from another connector. It doesn't work that well; it's easy to ruin them as you pull them out.
Problem #2: The directions were incorrect - one channel was working but the other wasn't. I called tech support again (this time on a weekend, the emergency tech support number), and the guy knew exactly what I needed to do to fix the problem - the wire needed to go in a different pin. It worked. However, we had to use silicone to get the wires to stick in the connector - they wanted to pull out easily.
Sitting in the driveway, everything worked fine after we resolved the above issues. It was quite another story when I actually tried to drive somewhere, though: the unit would constantly cut in and out, sometimes causing the receiver to switch back to the radio (at a higher volume, of course), and sometimes saying "CDX ERROR" (I think) on the display.
I called the company again, and they told me I needed a new "black box". A little explanation is in order here. The connector that goes into the back of your radio (or, in the Impala's case, to the wires behind the radio) is just a short (maybe a foot long) wire that connects to a black box with configuration switches on it. The other side of the black box has a connector for the changer's black cable to plug into, and the manual for the changer tells you what switches should be flipped.
The company shipped the new black box to me, after they offered to send me the software to update it myself if I didn't mind building the proper connector for my computer (I didn't take this route). I swapped the box a couple weeks later, and the situation improved drastically.
However, it's still not right. I still get engine noise through it, and it still occasionally cuts out and switches back to the radio. It does other odd things, too. For example, sometimes when I start the car, it'll start playing the song from the beginning instead of where it stopped. This is a minor concern and wouldn't bother me at all if it did it every time (because then I'd know it was supposed to do it!).
I'm going to try changing the ground and power source, on the assumption that I'm not getting "clean" power to the unit, which is causing both the engine whine and the occasional cut-out. I'll post the results here.
Update 6/24/06: It didn't help. I stoppped using the changer over a year ago and haven't missed it a single bit.