To be absolutely certain, you should:
* Consult your owner's manual: This is the best resource for the precise location in your specific vehicle.
* Look for a large, rectangular module with numerous connectors: The PCM is usually a fairly large electronic unit.
If you're having trouble locating it, a picture of your engine bay might help someone more familiar with the Aurora's layout provide a more precise answer. Remember to disconnect your vehicle's battery negative terminal before working near any electrical components.