Here are the best places to look:
* Chevrolet Parts Websites: Websites selling genuine GM parts (like gmpartsdirect.com or others linked through the official Chevrolet website) often have detailed parts diagrams. While not exploded in the truest sense, they are very detailed and might suffice. You'll need your Impala's VIN (Vehicle Identification Number) for precise part identification.
* Online Repair Manuals: Sites like AllDataDIY or Mitchell 1 offer online access to repair manuals, which often include more detailed parts diagrams than parts websites. These typically require a subscription fee.
* Haynes or Chilton Repair Manuals: These are physical repair manuals you can buy at auto parts stores or online. They usually have pretty good diagrams, though again, not necessarily fully exploded views.
* eBay or Amazon: You might find a scanned copy of a factory service manual on eBay or Amazon. These can sometimes contain higher-quality diagrams than readily available online. Be wary of low-quality scans though.
Keep in mind that a truly comprehensive exploded view, showing every nut, bolt, and washer, is usually not necessary for most repair jobs. The detailed parts diagrams available from the sources above are usually sufficient. If you need a highly specific exploded view, you may need to contact a specialized automotive parts supplier or a Chevy dealership directly.