1. Penetrating Oil and Patience:
* The Attempt: This is the first and best option. Liberally apply a penetrating oil (like PB Blaster, Kroil, or Liquid Wrench) into the keyhole and around the ignition switch housing. Let it soak for *hours*, even overnight, or even longer. Try working the key gently back and forth after each application. Heat from a hairdryer (on a low setting) *might* help the oil penetrate further, but be extremely cautious not to damage anything.
* Why it's important: Seizing is often due to corrosion or dried-up lubricant. Penetrating oil is your best chance to dissolve this.
2. Ignition Switch Removal (If Key Turns Slightly):
* The Attempt: If the key *turns slightly*, you might be able to remove the ignition switch assembly itself. This usually involves removing the steering wheel (a significant undertaking itself requiring specialized tools), then accessing the screws or nuts holding the ignition switch in place. Consult a 1957 Chevy repair manual for specifics. Once the switch is removed, you can work on the cylinder in a more accessible location.
* Why it's important: Removing the whole switch gives you better access and leverage to work on the cylinder.
3. Drilling Out the Cylinder (Destructive):
* The Attempt: This is a last resort. You'll need a small drill bit, ideally one slightly smaller than the cylinder's retaining pins or locking mechanism. Carefully drill out the retaining pins or the cylinder itself. This risks damage to the ignition switch housing and requires precision to avoid damaging other components. This method is highly NOT recommended unless you have experience working with ignition switches and are prepared for potential damage or replacement.
* Why it's the last resort: It's destructive, and you'll need a replacement lock cylinder afterwards.
4. Professional Locksmith:
* The Attempt: A locksmith specializing in classic cars is your best bet if the above methods fail. They have specialized tools and expertise to remove the cylinder without causing further damage. They might be able to manipulate the lock mechanism internally to release the cylinder.
* Why it's recommended: A locksmith will likely save you time, frustration, and potentially expensive repairs if you damage the ignition switch.
Important Considerations:
* Repair Manual: A 1957 Chevrolet repair manual is invaluable. It will show you how the ignition switch and cylinder are installed and provide diagrams.
* Safety: Disconnect the battery's negative terminal before starting any work to prevent electrical shocks.
* Parts: Be prepared to replace the ignition lock cylinder and possibly the ignition switch if it's damaged during the removal process. Finding parts for a 1957 Chevy might require some searching.
If you're not comfortable working with automotive electrical systems or mechanical components, strongly consider hiring a professional locksmith. The cost of a locksmith is much less than the cost of replacing damaged parts or the frustration of a failed DIY attempt.
