* Behind the brake booster: This is a popular spot because it often offers a relatively unobstructed path and is relatively close to the battery. However, you need to be very careful not to damage brake lines or other components. You'll likely need to use a grommet or create a carefully-sized hole to protect the wire.
* Near the clutch master cylinder (if applicable): Similar to the brake booster area, this location might offer a route, but requires careful attention to avoid damaging vital components. This option is only relevant if your Grand Prix has a manual transmission.
* Existing grommets or holes: Before drilling, carefully inspect the firewall for existing grommets or holes that might allow you to pass the wire through. Even a small opening can be used if you're careful.
Important Considerations:
* Rubber grommet: Always use a rubber grommet (or create a neatly-finished hole with a grommet installed) to protect the wire from chafing against the metal firewall and to prevent water intrusion.
* Wire size: Use an appropriately sized amp wire for your system's power requirements. Too small a wire can overheat and cause a fire.
* Protection: Secure the wire with zip ties or other suitable fasteners to prevent it from moving around and potentially shorting. Avoid routing the wire near moving parts or hot surfaces.
* Safety: Disconnect the negative terminal of your battery before starting any electrical work to prevent shorts or injury.
Recommendation: Before attempting any work, consult a repair manual specific to your 1997 Pontiac Grand Prix GT. These manuals often illustrate the firewall and suggest potential routing options. They might even show existing holes you can use. If you are uncomfortable with this type of work, seeking help from a professional automotive audio installer is the safest option.
