2004 Pontiac Grand Am factory stereo

You'll need to visit the dealer with these questions. GM had a 100 percent failure rate with their CD laser assemblies all through the '90s. They stopped allowing us to buy radio service manuals after the '94 model year because they wanted to lock up all that repair business for themselves. You were tied to the dealer and their two grossly over-priced repair centers. Instead, many people bought high-quality aftermarket radios rather than pay between $400.00 and $450.00 to have a factory radio repaired. To combat that, the GM engineers cleverly built the Body Computer into the radios starting with some 2002 truck models. You had to keep the factory radio in there. They even devised a way to prevent you from buying a used radio from the salvage yard. If that worked, you still had to have the dealer program it to your car, and they sure don't do that for free.

I don't recall seeing a combo CD / cassette in any early 2000s GM product. There may have been something available, but I only know those were real common in mid 90s Chryslers and late 90s Fords. The dealer will know what is available. If no one in the parts department is able to find the replacement you're looking for, try a second dealer. Some of them just look at "standard issue" models and don't bother to research what else might be available from the manufacturer. You may need to go to a newer model, not an older one.